diff --git a/lib/bcoin/address.js b/lib/bcoin/address.js
index 0f74008b..177160a9 100644
--- a/lib/bcoin/address.js
+++ b/lib/bcoin/address.js
@@ -42,16 +42,11 @@ function Address(options) {
   this.keys = [];
   this.m = options.m || 1;
   this.n = options.n || 1;
-  this.redeem = null;
 
   if (this.n > 1)
     this.type = 'multisig';
 
   assert(this.type === 'pubkeyhash' || this.type === 'multisig');
-  this.prefixType = this.type === 'multisig' ? 'scripthash' : 'pubkeyhash';
-
-  if (network.address.prefixes[this.prefixType] == null)
-    throw new Error('Unknown prefix: ' + this.prefixType);
 
   if (this.m < 1 || this.m > this.n)
     throw new Error('m ranges between 1 and n');
@@ -61,9 +56,6 @@ function Address(options) {
   (options.keys || []).forEach(function(key) {
     this.addKey(key);
   }, this);
-
-  if (options.redeem || options.script)
-    this.setRedeem(options.redeem || options.script);
 }
 
 utils.inherits(Address, EventEmitter);
@@ -100,22 +92,7 @@ Address.prototype.getBalance = function getBalance() {
   return this._wallet.getBalance(this);
 };
 
-Address.prototype.setRedeem = function setRedeem(redeem) {
-  var old = this.getScriptAddress();
-
-  if (!Buffer.isBuffer(redeem))
-    redeem = bcoin.script.encode(redeem);
-
-  this.type = 'multisig';
-  this.prefixType = 'scripthash';
-  this.redeem = redeem;
-  this.emit('update script', old, this.getScriptAddress());
-};
-
 Address.prototype.addKey = function addKey(key) {
-  var old = this.getScriptAddress();
-  var cur;
-
   key = utils.ensureBuffer(key);
 
   var has = this.keys.some(function(k) {
@@ -128,22 +105,9 @@ Address.prototype.addKey = function addKey(key) {
   this.keys.push(key);
 
   this.keys = utils.sortKeys(this.keys);
-
-  delete this._scriptAddress;
-  delete this._scriptHash;
-  delete this._script;
-  this.getScriptAddress();
-
-  cur = this.getScriptAddress();
-
-  if (old !== cur)
-    this.emit('update script', old, cur);
 };
 
 Address.prototype.removeKey = function removeKey(key) {
-  var old = this.getScriptAddress();
-  var cur;
-
   key = utils.ensureBuffer(key);
 
   var index = this.keys.map(function(k, i) {
@@ -158,16 +122,6 @@ Address.prototype.removeKey = function removeKey(key) {
   this.keys.splice(index, 1);
 
   this.keys = utils.sortKeys(this.keys);
-
-  delete this._scriptAddress;
-  delete this._scriptHash;
-  delete this._script;
-  this.getScriptAddress();
-
-  cur = this.getScriptAddress();
-
-  if (old !== cur)
-    this.emit('update script', old, cur);
 };
 
 Address.prototype.getPrivateKey = function getPrivateKey(enc) {
@@ -177,65 +131,122 @@ Address.prototype.getPrivateKey = function getPrivateKey(enc) {
 Address.prototype.getScript = function getScript() {
   var redeem;
 
-  if (this.prefixType !== 'scripthash')
+  if (this.type !== 'multisig')
     return;
 
   if (this._script)
     return this._script;
 
-  if (this.redeem) {
-    redeem = this.redeem;
-    assert(Buffer.isBuffer(redeem));
-  } else if (this.keys.length < this.n) {
-    redeem = bcoin.script.createPubkeyhash(this.getKeyHash());
-    redeem = bcoin.script.encode(redeem);
-  } else {
-    redeem = bcoin.script.createMultisig(this.keys, this.m, this.n);
-    redeem = bcoin.script.encode(redeem);
-  }
+  assert(this.keys.length === this.n, 'Not all keys have been added.');
 
-  if (redeem.length > 520)
-    throw new Error('Redeem script too large (520 byte limit).');
+  redeem = bcoin.script.createMultisig(this.keys, this.m, this.n);
+  redeem = bcoin.script.encode(redeem);
+
+  if (this.options.program) {
+    if (redeem.length > 10000)
+      throw new Error('Redeem script too large (10000 byte limit).');
+  } else {
+    if (redeem.length > 520)
+      throw new Error('Redeem script too large (520 byte limit).');
+  }
 
   this._script = redeem;
 
   return this._script;
 };
 
-Address.prototype.getScriptHash = function getScriptHash() {
-  if (this.prefixType !== 'scripthash')
+Address.prototype.getProgram = function getProgram() {
+  var program;
+
+  if (!this.options.program)
     return;
 
-  if (this._scriptHash)
-    return this._scriptHash;
+  if (this._program)
+    return this._program;
 
-  this._scriptHash = Address.hash160(this.getScript());
+  if (this.type === 'pubkeyhash') {
+    program = bcoin.script.createWitnessProgram(
+      0, Address.hash160(this.getPublicKey()));
+  } else if (this.type === 'multisig') {
+    program = bcoin.script.createWitnessProgram(
+      0, utils.sha256(this.getScript()));
+  }
 
-  return this._scriptHash;
+  assert(program);
+
+  this._program = bcoin.script.encode(program);
+
+  return this._program;
+};
+
+Address.prototype.getProgramHash = function getProgramHash() {
+  if (!this.options.program)
+    return;
+
+  if (this._programHash)
+    return this._programHash;
+
+  this._programHash = Address.hash160(this.getProgram());
+
+  return this._programHash;
+};
+
+Address.prototype.getProgramAddress = function getProgramAddress() {
+  if (!this.options.program)
+    return;
+
+  if (this._programAddress)
+    return this._programAddress;
+
+  this._programAddress = Address.compileHash(this.getProgramHash(), 'scripthash');
+
+  return this._programAddress;
+};
+
+Address.prototype.getScriptHash = function getScriptHash() {
+  return this.getScriptHash160();
+};
+
+Address.prototype.getScriptHash160 = function getScriptHash256() {
+  if (this.type !== 'multisig')
+    return;
+
+  if (this._scriptHash160)
+    return this._scriptHash160;
+
+  this._scriptHash160 = Address.hash160(this.getScript());
+
+  return this._scriptHash160;
+};
+
+Address.prototype.getScriptHash256 = function getScriptHash256() {
+  if (this.type !== 'multisig')
+    return;
+
+  if (this._scriptHash256)
+    return this._scriptHash256;
+
+  this._scriptHash256 = Address.sha256(this.getScript());
+
+  return this._scriptHash256;
 };
 
 Address.prototype.getScriptAddress = function getScriptAddress() {
-  if (this.prefixType !== 'scripthash')
+  if (this.type !== 'multisig')
     return;
 
   if (this._scriptAddress)
     return this._scriptAddress;
 
-  this._scriptAddress = Address.compileHash(this.getScriptHash(), this.prefixType);
+  if (this.options.program)
+    this._scriptAddress = Address.compileHash(this.getScriptHash256(), 'witnessscripthash');
+  else
+    this._scriptAddress = Address.compileHash(this.getScriptHash160(), 'scripthash');
 
   return this._scriptAddress;
 };
 
 Address.prototype.getPublicKey = function getPublicKey(enc) {
-  if (!enc) {
-    if (this._pub)
-      return this._pub;
-
-    this._pub = this.key.getPublicKey();
-
-    return this._pub;
-  }
-
   return this.key.getPublicKey(enc);
 };
 
@@ -252,19 +263,22 @@ Address.prototype.getKeyAddress = function getKeyAddress() {
   if (this._address)
     return this._address;
 
-  this._address = Address.compileHash(this.getKeyHash(), 'pubkeyhash');
+  if (this.options.program)
+    this._address = Address.compileHash(this.getKeyHash(), 'witnesspubkeyhash');
+  else
+    this._address = Address.compileHash(this.getKeyHash(), 'pubkeyhash');
 
   return this._address;
 };
 
 Address.prototype.getHash = function getHash() {
-  if (this.prefixType === 'scripthash')
+  if (this.type === 'multisig')
     return this.getScriptHash();
   return this.getKeyHash();
 };
 
 Address.prototype.getAddress = function getAddress() {
-  if (this.prefixType === 'scripthash')
+  if (this.type === 'multisig')
     return this.getScriptAddress();
   return this.getKeyAddress();
 };
@@ -277,9 +291,12 @@ Address.prototype._getAddressMap = function _getAddressMap() {
 
   this.addressMap[this.getKeyAddress()] = true;
 
-  if (this.prefixType === 'scripthash')
+  if (this.type === 'multisig')
     this.addressMap[this.getScriptAddress()] = true;
 
+  if (this.options.program)
+    this.addressMap[this.getProgramAddress()] = true;
+
   return this.addressMap;
 };
 
@@ -351,7 +368,7 @@ Address.prototype.scriptInputs = function scriptInputs(tx, index) {
     if (!self.ownOutput(input.output))
       return total;
 
-    if (tx.scriptInput(i, publicKey, redeem))
+    if (tx.scriptInput(i, self))
       total++;
 
     return total;
@@ -379,7 +396,7 @@ Address.prototype.signInputs = function signInputs(tx, type, index) {
     if (!self.ownOutput(input.output))
       return total;
 
-    if (tx.signInput(i, key, type))
+    if (tx.signInput(i, self, type))
       total++;
 
     return total;
@@ -409,7 +426,7 @@ Address.prototype.sign = function sign(tx, type, index) {
     if (!self.ownOutput(input.output))
       return total;
 
-    if (tx.sign(i, key, redeem, type))
+    if (tx.sign(i, self, type))
       total++;
 
     return total;
@@ -424,10 +441,30 @@ Address.prototype.__defineGetter__('scriptHash', function() {
   return this.getScriptHash();
 });
 
+Address.prototype.__defineGetter__('scriptHash160', function() {
+  return this.getScriptHash160();
+});
+
+Address.prototype.__defineGetter__('scriptHash256', function() {
+  return this.getScriptHash256();
+});
+
 Address.prototype.__defineGetter__('scriptAddress', function() {
   return this.getScriptAddress();
 });
 
+Address.prototype.__defineGetter__('program', function() {
+  return this.getProgram();
+});
+
+Address.prototype.__defineGetter__('programHash', function() {
+  return this.getProgramHash();
+});
+
+Address.prototype.__defineGetter__('programAddress', function() {
+  return this.getProgramAddress();
+});
+
 Address.prototype.__defineGetter__('privateKey', function() {
   return this.getPrivateKey();
 });
diff --git a/lib/bcoin/chain.js b/lib/bcoin/chain.js
index d27c1372..aabf97e7 100644
--- a/lib/bcoin/chain.js
+++ b/lib/bcoin/chain.js
@@ -455,7 +455,7 @@ Chain.prototype._verifyContext = function _verifyContext(block, prev, callback)
 Chain.prototype._verify = function _verify(block, prev) {
   var flags = constants.flags.MANDATORY_VERIFY_FLAGS;
   var height, ts, i, tx, cb, coinbaseHeight, medianTime;
-  var locktimeMedian, coinbase, commitment, segwit;
+  var locktimeMedian, segwit;
 
   if (!block.verify())
     return flags;
@@ -575,11 +575,16 @@ Chain.prototype._verify = function _verify(block, prev) {
     }
   }
 
-  if (segwit) {
-    if (block._witness && block.commitmentHash !== block.getCommitmentHash()) {
+  if (block.version >= 5 && segwit) {
+    if (block.commitmentHash !== block.getCommitmentHash()) {
       utils.debug('Block failed witnessroot test: %s', block.rhash);
       return false;
     }
+  } else {
+    if (block.hasWitness()) {
+      utils.debug('Unexpected witness data found: %s', block.rhash);
+      return false;
+    }
   }
 
   // Get timestamp for tx.isFinal().
@@ -655,11 +660,11 @@ Chain.prototype._checkInputs = function _checkInputs(block, prev, flags, callbac
     var i, j, input, hash;
     var sigops = 0;
 
-    utils.print(height);
-    utils.print(block.commitmentHash ? utils.revHex(block.commitmentHash) : null);
-    utils.print(utils.revHex(block.getCommitmentHash() || '00'));
-    utils.print(block.txs[0]);
-    utils.print(block.txs[1]);
+    // utils.print(height);
+    // utils.print(block.commitmentHash ? utils.revHex(block.commitmentHash) : null);
+    // utils.print(utils.revHex(block.getCommitmentHash() || '00'));
+    // utils.print(block.txs[0]);
+    // utils.print(block.txs[1]);
 
     if (err)
       return callback(err);
@@ -704,6 +709,9 @@ Chain.prototype._checkInputs = function _checkInputs(block, prev, flags, callbac
             throw new Error('BUG: Bad inputs in historical data!');
           return callback(null, false);
         }
+
+        if (input.output.getType() === 'scripthash')
+          utils.debug(tx);
       }
 
       if (!scriptCheck)
diff --git a/lib/bcoin/mempool.js b/lib/bcoin/mempool.js
index 5a98b35a..486523c7 100644
--- a/lib/bcoin/mempool.js
+++ b/lib/bcoin/mempool.js
@@ -207,6 +207,9 @@ Mempool.prototype.addTX = function addTX(tx, peer, callback) {
   if (tx.isCoinbase())
     return callback(new Error('What?'));
 
+  if (!this.checkTX(tx, peer))
+    return callback(new Error('TX failed checkTX.'));
+
   assert(tx.ts === 0);
 
   this._lockTX(tx);
@@ -219,6 +222,9 @@ Mempool.prototype.addTX = function addTX(tx, peer, callback) {
     if (err)
       return callback(err);
 
+    // Do this in the future.
+    // tx = self.fillCoin(tx);
+
     if (!tx.hasPrevout()) {
       return callback(new Error('Previous outputs not found.'));
       peer.reject({
@@ -465,6 +471,67 @@ Mempool.prototype.unlock = function unlock() {
   this.locked = false;
 };
 
+Mempool.prototype.checkTX = function checkTX(tx, peer) {
+  var i, input, output, size;
+  var total = new bn(0);
+  var uniq = {};
+
+  if (tx.inputs.length === 0)
+    return this.reject(peer, tx, 'bad-txns-vin-empty');
+
+  if (tx.outputs.length === 0)
+    return this.reject(peer, tx, 'bad-txns-vout-empty');
+
+  if (tx.getSize() > constants.block.maxSize)
+    return this.reject(peer, tx, 'bad-txns-oversize');
+
+  for (i = 0; i < tx.outputs.length; i++) {
+    output = tx.outputs[i];
+    if (output.value.cmpn(0) < 0)
+      return this.reject(peer, tx, 'bad-txns-vout-negative');
+    if (output.value.cmp(constants.maxMoney) > 0)
+      return this.reject(peer, tx, 'bad-txns-vout-toolarge');
+    total.iadd(output.value);
+    if (total.cmpn(0) < 0 || total.cmp(constants.maxMoney))
+      return this.reject(peer, tx, 'bad-txns-txouttotal-toolarge');
+  }
+
+  for (i = 0; i < tx.inputs.length; i++) {
+    input = tx.inputs[i];
+    if (uniq[input.out.hash])
+      return this.reject(peer, tx, 'bad-txns-inputs-duplicate');
+    uniq[input.out.hash] = true;
+  }
+
+  if (tx.isCoinbase()) {
+    size = bcoin.script.getSize(tx.inputs[0].script);
+    if (size < 2 || size > 100)
+      return this.reject(peer, tx, 'bad-cb-length');
+  } else {
+    for (i = 0; i < tx.inputs.length; i++) {
+      input = tx.inputs[i];
+      if (+input.out.hash === 0)
+        return this.reject(peer, tx, 'bad-txns-prevout-null');
+    }
+  }
+
+  return true;
+};
+
+Mempool.prototype.reject = function reject(peer, obj, reason) {
+  return false;
+
+  if (!peer)
+    return false;
+
+  peer.reject({
+    reason: reason,
+    data: obj.hash ? obj.hash() : []
+  });
+
+  return false;
+};
+
 /**
  * Expose
  */
diff --git a/lib/bcoin/mtx.js b/lib/bcoin/mtx.js
index 5a44e741..61c097ef 100644
--- a/lib/bcoin/mtx.js
+++ b/lib/bcoin/mtx.js
@@ -67,6 +67,7 @@ MTX.prototype.clone = function clone() {
 
   tx.inputs = tx.inputs.map(function(input) {
     input.script = input.script.slice();
+    input.witness = input.witness.slice();
     return input;
   });
 
@@ -129,8 +130,8 @@ MTX.prototype.addInput = function addInput(options, index) {
   return this;
 };
 
-MTX.prototype.scriptInput = function scriptInput(index, publicKey, redeem) {
-  var input, s, n, i;
+MTX.prototype.scriptInput = function scriptInput(index, addr) {
+  var input, prev, n, i, redeemScript, witnessScript, vector, dummy;
 
   if (typeof index !== 'number')
     index = this.inputs.indexOf(index);
@@ -139,102 +140,173 @@ MTX.prototype.scriptInput = function scriptInput(index, publicKey, redeem) {
   input = this.inputs[index];
   assert(input);
 
-  // Already has a script template (at least)
-  // if (input.script.length)
-  //   return;
-
   // We should have previous outputs by now.
   assert(input.output);
 
-  // Get the previous output's subscript
-  s = input.output.script;
+  // Optimization: Don't bother with any below
+  // calculation if the output is already templated.
+  // Just say this is "our" output.
+  if (input.script.length || input.witness.length)
+    return true;
 
-  // P2SH
-  if (bcoin.script.isScripthash(s)) {
-    if (!redeem)
+  // Optimization: test output against the
+  // address map to avoid unnecessary calculation.
+  // A hash table lookup may be faster than all
+  // the nonsense below.
+  if (!addr.ownOutput(input.output))
+    return false;
+
+  // Get the previous output's script
+  prev = input.output.script;
+
+  // This is easily the hardest part about building a transaction
+  // with segwit: figuring out where the redeem script and witness
+  // redeem scripts go.
+  if (bcoin.script.isScripthash(prev)) {
+    if (addr.program && utils.isEqual(prev[1], addr.programHash)) {
+      // Witness program nested in regular P2SH.
+      redeemScript = addr.program;
+      vector = input.witness;
+      dummy = new Buffer([]);
+      assert(addr.program[0] === 0, 'Non-zero version passed to address.');
+      if (addr.program.length === 34) {
+        // P2WSH nested within pay-to-scripthash
+        // (it had to be this complicated, didn't it?)
+        witnessScript = addr.script;
+        prev = bcoin.script.decode(addr.script);
+      } else if (addr.program.length === 22) {
+        // P2WPKH nested within pay-to-scripthash.
+        prev = bcoin.script.createPubkeyhash(addr.keyHash);
+      } else {
+        assert(false, 'Unknown program data length passed to address.');
+      }
+    } else if (addr.script && utils.isEqual(prev[1], addr.scriptHash160)) {
+      // Regular P2SH.
+      redeemScript = addr.script;
+      prev = bcoin.script.decode(addr.script);
+      vector = input.script;
+      dummy = 0;
+    } else {
       return false;
-    s = bcoin.script.decode(redeem);
+    }
+  } else if (bcoin.script.isWitnessProgram(prev)) {
+    // Witness program.
+    vector = input.witness;
+    dummy = new Buffer([]);
+
+    if (prev[0] !== 0)
+      return false;
+
+    if (prev[1].length === 32) {
+      // Bare P2WPSH.
+      if (!addr.script || !utils.isEqual(prev[1], addr.scriptHash256))
+        return false;
+
+      witnessScript = addr.script;
+      prev = bcoin.script.decode(addr.script);
+    } else if (prev[1].length === 20) {
+      // Bare P2WPKH.
+      if (!utils.isEqual(prev[1], addr.keyHash))
+        return false;
+
+      prev = bcoin.script.createPubkeyhash(prev[1]);
+    } else {
+      // Bare... who knows?
+      return false;
+    }
   } else {
-    redeem = null;
+    // Wow, a normal output! Praise be to Jengus and Gord.
+    vector = input.script;
+    dummy = 0;
   }
 
-  if (bcoin.script.isPubkey(s)) {
+  if (bcoin.script.isPubkey(prev)) {
     // P2PK
-    if (!utils.isEqual(s[0], publicKey))
+    if (!utils.isEqual(prev[0], addr.publicKey))
       return false;
+
     // Already has a script template (at least)
-    if (input.script.length)
+    if (vector.length)
       return true;
-    input.script = [0];
-  } else if (bcoin.script.isPubkeyhash(s)) {
+
+    vector[0] = dummy;
+  } else if (bcoin.script.isPubkeyhash(prev)) {
     // P2PKH
-    if (!utils.isEqual(s[2], bcoin.address.hash160(publicKey)))
+    if (!utils.isEqual(prev[2], addr.keyHash))
       return false;
+
     // Already has a script template (at least)
-    if (input.script.length)
+    if (vector.length)
       return true;
-    input.script = [0, publicKey];
-  } else if (bcoin.script.isMultisig(s)) {
+
+    vector[0] = dummy;
+    vector[1] = addr.publicKey;
+  } else if (bcoin.script.isMultisig(prev)) {
     // Multisig
-    for (i = 0; i < s.length; i++) {
-      if (utils.isEqual(s[i], publicKey))
+    for (i = 0; i < prev.length; i++) {
+      if (utils.isEqual(prev[i], addr.publicKey))
         break;
     }
 
-    if (i === s.length)
+    if (i === prev.length)
       return false;
 
     // Already has a script template (at least)
-    if (input.script.length)
+    if (vector.length)
       return true;
 
     // Technically we should create m signature slots,
     // but we create n signature slots so we can order
     // the signatures properly.
-    input.script = [0];
+    vector[0] = dummy;
 
     // Grab `n` value (number of keys).
-    n = s[s.length - 2];
+    n = prev[prev.length - 2];
 
     // Fill script with `n` signature slots.
     for (i = 0; i < n; i++)
-      input.script[i + 1] = 0;
+      vector[i + 1] = dummy;
   } else {
-    for (i = 0; i < s.length; i++) {
-      if (utils.isEqual(s[i], publicKey))
+    for (i = 0; i < prev.length; i++) {
+      if (utils.isEqual(prev[i], addr.publicKey))
         break;
     }
 
-    if (i === s.length)
+    if (i === prev.length)
       return false;
 
     // Already has a script template (at least)
-    if (input.script.length)
+    if (vector.length)
       return true;
 
     // Likely a non-standard scripthash multisig
     // input. Determine n value by counting keys.
     // Also, only allow nonstandard types for
     // scripthash.
-    if (redeem) {
-      input.script = [0];
-      // Fill script with `n` signature slots.
-      for (i = 0; i < s.length; i++) {
-        if (bcoin.script.isKey(s[i]))
-          input.script.push(0);
-      }
+    vector[0] = dummy;
+
+    // Fill script with `n` signature slots.
+    for (i = 0; i < prev.length; i++) {
+      if (bcoin.script.isKey(prev[i]))
+        vector[i + 1] = dummy;
     }
   }
 
-  // P2SH requires the redeem script after signatures
-  if (redeem)
-    input.script.push(redeem);
+  // P2SH requires the redeem
+  // script after signatures.
+  if (redeemScript)
+    input.script.push(redeemScript);
+
+  // P2WSH requires the witness
+  // script after signatures.
+  if (witnessScript)
+    input.witness.push(witnessScript);
 
   return true;
 };
 
-MTX.prototype.createSignature = function createSignature(index, key, type) {
-  var input, s, hash, signature;
+MTX.prototype.createSignature = function createSignature(index, prev, key, type) {
+  var prev, hash, signature;
 
   if (typeof index !== 'number')
     index = this.inputs.indexOf(index);
@@ -245,38 +317,22 @@ MTX.prototype.createSignature = function createSignature(index, key, type) {
   if (typeof type === 'string')
     type = constants.hashType[type];
 
-  // Get the input
-  input = this.inputs[index];
-  assert(input);
-
-  // We should have previous outputs by now.
-  assert(input.output);
-
-  // Get the previous output's subscript
-  s = input.output.script;
-
-  // We need to grab the redeem script when
-  // signing p2sh transactions.
-  if (bcoin.script.isScripthash(s))
-    s = bcoin.script.getRedeem(input.script);
-
   // Get the hash of the current tx, minus the other
   // inputs, plus the sighash type.
-  hash = this.signatureHash(index, s, type);
+  hash = this.signatureHash(index, prev, type);
 
   // Sign the transaction with our one input
   signature = bcoin.script.sign(hash, key, type);
 
   // Something is broken if this doesn't work:
-  assert(bcoin.script.checksig(hash, signature, key));
+  // assert(bcoin.script.checksig(hash, signature, key), 'BUG: Verify failed.');
 
   return signature;
 };
 
-// Sign the now-built scriptSigs
-MTX.prototype.signInput = function signInput(index, key, type) {
-  var input, s, signature, ki, signatures, i;
-  var len, m, n, keys, publicKey, keyHash;
+MTX.prototype.signInput = function signInput(index, addr, type) {
+  var input, prev, signature, ki, signatures, i;
+  var len, m, n, keys, vector, dummy;
 
   if (typeof index !== 'number')
     index = this.inputs.indexOf(index);
@@ -288,87 +344,103 @@ MTX.prototype.signInput = function signInput(index, key, type) {
   // We should have previous outputs by now.
   assert(input.output);
 
-  // Create our signature.
-  signature = this.createSignature(index, key, type);
-
   // Get the previous output's subscript
-  s = input.output.script;
+  prev = input.output.script;
 
-  // Script length, needed for multisig
-  len = input.script.length;
+  vector = input.script;
+  len = vector.length;
+  dummy = 0;
 
   // We need to grab the redeem script when
   // signing p2sh transactions.
-  if (bcoin.script.isScripthash(s)) {
-    s = bcoin.script.getRedeem(input.script);
-    // Decrement `len` to avoid the redeem script
-    len--;
+  if (bcoin.script.isScripthash(prev)) {
+    prev = bcoin.script.getRedeem(input.script);
+    len = vector.length - 1;
   }
 
-  // Get pubkey.
-  publicKey = key.getPublicKey();
+  // If the output script is a witness program,
+  // we have to switch the vector to the witness
+  // and potentially alter the length. Note that
+  // witnesses are stack items, so the `dummy`
+  // _has_ to be an empty buffer (what OP_0
+  // pushes onto the stack).
+  if (bcoin.script.isWitnessScripthash(prev)) {
+    prev = bcoin.script.getRedeem(input.witness);
+    vector = input.witness;
+    len = vector.length - 1;
+    dummy = new Buffer([]);
+  } else if (bcoin.script.isWitnessPubkeyhash(prev)) {
+    prev = bcoin.script.createPubkeyhash(prev[1]);
+    vector = input.witness;
+    len = vector.length;
+    dummy = new Buffer([]);
+  }
+
+  // Create our signature.
+  signature = this.createSignature(index, prev, addr.key, type);
 
   // Add signatures.
-  if (bcoin.script.isPubkey(s)) {
+  if (bcoin.script.isPubkey(prev)) {
     // P2PK
 
     // Already signed.
-    if (bcoin.script.isSignature(input.script[0]))
+    if (bcoin.script.isSignature(vector[0]))
       return true;
 
     // Make sure the pubkey is ours.
-    if (!utils.isEqual(publicKey, s[0]))
+    if (!utils.isEqual(addr.publicKey, prev[0]))
       return false;
 
-    input.script[0] = signature;
+    vector[0] = signature;
 
     return true;
   }
 
-  if (bcoin.script.isPubkeyhash(s)) {
+  if (bcoin.script.isPubkeyhash(prev)) {
     // P2PKH
 
     // Already signed.
-    if (bcoin.script.isSignature(input.script[0]))
+    if (bcoin.script.isSignature(vector[0]))
       return true;
 
     // Make sure the pubkey hash is ours.
-    keyHash = bcoin.address.hash160(publicKey);
-    if (!utils.isEqual(keyHash, s[2]))
+    if (!utils.isEqual(addr.keyHash, prev[2]))
       return false;
 
-    input.script[0] = signature;
+    vector[0] = signature;
 
     return true;
   }
 
-  if (bcoin.script.isMultisig(s)) {
+  if (bcoin.script.isMultisig(prev)) {
     // Multisig
 
     // Grab the redeem script's keys to figure
     // out where our key should go.
-    keys = s.slice(1, -2);
+    keys = prev.slice(1, -2);
 
     // Grab `m` value (number of sigs required).
-    m = s[0];
+    m = prev[0];
 
     // Grab `n` value (number of keys).
-    n = s[s.length - 2];
+    n = prev[prev.length - 2];
   } else {
     // Only allow non-standard signing for
     // scripthash.
-    if (len !== input.script.length - 1)
+    if (len !== vector.length - 1)
       return false;
 
     keys = [];
 
-    for (i = 0; i < s.length; i++) {
-      if (bcoin.script.isKey(s[i]))
-        keys.push(s[i]);
+    for (i = 0; i < prev.length; i++) {
+      if (bcoin.script.isKey(prev[i]))
+        keys.push(prev[i]);
     }
 
+    // We don't know what m is, so
+    // we can never finalize the signatures.
+    m = keys.length;
     n = keys.length;
-    m = n;
   }
 
   // Something is very wrong here. Abort.
@@ -378,7 +450,7 @@ MTX.prototype.signInput = function signInput(index, key, type) {
   // Count the number of current signatures.
   signatures = 0;
   for (i = 1; i < len; i++) {
-    if (bcoin.script.isSignature(input.script[i]))
+    if (bcoin.script.isSignature(vector[i]))
       signatures++;
   }
 
@@ -391,14 +463,14 @@ MTX.prototype.signInput = function signInput(index, key, type) {
   // or by `m`. Add some signature slots for
   // us to use.
   while (len - 1 < n) {
-    input.script.splice(len, 0, 0);
+    vector.splice(len, 0, dummy);
     len++;
   }
 
   // Find the key index so we can place
   // the signature in the same index.
   for (ki = 0; ki < keys.length; ki++) {
-    if (utils.isEqual(publicKey, keys[ki]))
+    if (utils.isEqual(addr.publicKey, keys[ki]))
       break;
   }
 
@@ -417,8 +489,8 @@ MTX.prototype.signInput = function signInput(index, key, type) {
   // and increment the total number of
   // signatures.
   if (ki < len && signatures < m) {
-    if (input.script[ki] === 0) {
-      input.script[ki] = signature;
+    if (bcoin.script.isZero(vector[ki])) {
+      vector[ki] = signature;
       signatures++;
     }
   }
@@ -427,8 +499,8 @@ MTX.prototype.signInput = function signInput(index, key, type) {
   if (signatures >= m) {
     // Remove empty slots left over.
     for (i = len - 1; i >= 1; i--) {
-      if (input.script[i] === 0) {
-        input.script.splice(i, 1);
+      if (bcoin.script.isZero(vector[i])) {
+        vector.splice(i, 1);
         len--;
       }
     }
@@ -438,7 +510,7 @@ MTX.prototype.signInput = function signInput(index, key, type) {
     // with implementations that potentially handle
     // signature slots differently.
     while (signatures > m) {
-      input.script.splice(len - 1, 1);
+      vector.splice(len - 1, 1);
       signatures--;
       len--;
     }
@@ -451,8 +523,7 @@ MTX.prototype.signInput = function signInput(index, key, type) {
   return signatures === m;
 };
 
-MTX.prototype.sign = function sign(index, key, redeem, type) {
-  var publicKey = key.getPublicKey();
+MTX.prototype.sign = function sign(index, addr, type) {
   var input;
 
   if (index && typeof index === 'object')
@@ -462,104 +533,16 @@ MTX.prototype.sign = function sign(index, key, redeem, type) {
   assert(input);
 
   // Build script for input
-  if (!this.scriptInput(index, publicKey, redeem))
+  if (!this.scriptInput(index, addr))
     return false;
 
   // Sign input
-  if (!this.signInput(index, key, type))
+  if (!this.signInput(index, addr, type))
     return false;
 
   return true;
 };
 
-MTX.prototype.isSigned = function isSigned(index, required) {
-  var i, input, s, len, m, j, total;
-
-  if (this._signed)
-    return true;
-
-  if (index && typeof index === 'object')
-    index = this.inputs.indexOf(index);
-
-  if (index != null)
-    assert(this.inputs[index]);
-
-  for (i = 0; i < this.inputs.length; i++) {
-    input = this.inputs[i];
-
-    if (index != null && i !== index)
-      continue;
-
-    // We can't check for signatures unless
-    // we have the previous output.
-    assert(input.output);
-
-    // Get the prevout's subscript
-    s = input.output.script;
-
-    // Script length, needed for multisig
-    len = input.script.length;
-
-    // Grab the redeem script if P2SH
-    if (bcoin.script.isScripthash(s)) {
-      s = bcoin.script.getRedeem(input.script);
-      // Decrement `len` to avoid the redeem script
-      len--;
-    }
-
-    // Check for signatures.
-    // P2PK
-    if (bcoin.script.isPubkey(s)) {
-      if (!bcoin.script.isSignature(input.script[0]))
-        return false;
-      continue;
-    }
-
-    // P2PK
-    if (bcoin.script.isPubkeyhash(s)) {
-      if (!bcoin.script.isSignature(input.script[0]))
-        return false;
-      continue;
-    }
-
-    // Multisig
-    if (bcoin.script.isMultisig(s)) {
-      // Grab `m` value (number of required sigs).
-      m = s[0];
-      if (Buffer.isBuffer(m))
-        m = m[0] || 0;
-
-      // Ensure all members are signatures.
-      for (j = 1; j < len; j++) {
-        if (!bcoin.script.isSignature(input.script[j]))
-          return false;
-      }
-
-      // Ensure we have the correct number
-      // of required signatures.
-      if (len - 1 !== m)
-        return false;
-
-      continue;
-    }
-
-    if (required == null)
-      continue;
-
-    // Unknown
-    total = 0;
-    for (j = 0; j < input.script.length; j++) {
-      if (bcoin.script.isSignatureEncoding(input.script[j]))
-        total++;
-    }
-
-    if (total !== required)
-      return false;
-  }
-
-  return this._signed = true;
-};
-
 MTX.prototype.addOutput = function addOutput(obj, value) {
   var options, output;
 
@@ -667,7 +650,7 @@ MTX.prototype.scriptOutput = function scriptOutput(index, options) {
 
 MTX.prototype.maxSize = function maxSize(maxM, maxN) {
   var copy = this.clone();
-  var i, j, input, total, size, s, m, n;
+  var i, j, input, total, size, prev, m, n;
 
   // Create copy with 0-script inputs
   for (i = 0; i < copy.inputs.length; i++)
@@ -683,38 +666,38 @@ MTX.prototype.maxSize = function maxSize(maxM, maxN) {
     assert(input.output);
 
     // Get the previous output's subscript
-    s = input.output.script;
+    prev = input.output.script;
 
     // If we have access to the redeem script,
     // we can use it to calculate size much easier.
-    if (this.inputs[i].script.length && bcoin.script.isScripthash(s)) {
-      s = bcoin.script.getRedeem(this.inputs[i].script);
+    if (this.inputs[i].script.length && bcoin.script.isScripthash(prev)) {
+      prev = bcoin.script.getRedeem(this.inputs[i].script);
       // Need to add the redeem script size
       // here since it will be ignored by
       // the isMultisig clause.
       // OP_PUSHDATA2 [redeem]
-      size += 3 + bcoin.script.getSize(s);
+      size += 3 + bcoin.script.getSize(prev);
     }
 
-    if (bcoin.script.isPubkey(s)) {
+    if (bcoin.script.isPubkey(prev)) {
       // P2PK
       // OP_PUSHDATA0 [signature]
       size += 1 + 73;
-    } else if (bcoin.script.isPubkeyhash(s)) {
+    } else if (bcoin.script.isPubkeyhash(prev)) {
       // P2PKH
       // OP_PUSHDATA0 [signature]
       size += 1 + 73;
       // OP_PUSHDATA0 [key]
       size += 1 + 33;
-    } else if (bcoin.script.isMultisig(s)) {
+    } else if (bcoin.script.isMultisig(prev)) {
       // Bare Multisig
       // Get the previous m value:
-      m = s[0];
+      m = prev[0];
       // OP_0
       size += 1;
       // OP_PUSHDATA0 [signature] ...
       size += (1 + 73) * m;
-    } else if (bcoin.script.isScripthash(s)) {
+    } else if (bcoin.script.isScripthash(prev)) {
       // P2SH Multisig
       // This technically won't work well for other
       // kinds of P2SH. It will also over-estimate
@@ -744,8 +727,8 @@ MTX.prototype.maxSize = function maxSize(maxM, maxN) {
       size += 1;
     } else {
       // OP_PUSHDATA0 [signature]
-      for (j = 0; j < s.length; j++) {
-        if (bcoin.script.isKey(s[j]))
+      for (j = 0; j < prev.length; j++) {
+        if (bcoin.script.isKey(prev[j]))
           size += 1 + 73;
       }
     }
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index 536632fc..0535851d 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -1260,13 +1260,21 @@ Pool.prototype.removeWallet = function removeWallet(wallet) {
 };
 
 Pool.prototype.watchAddress = function watchAddress(address) {
-  if (address.type === 'scripthash') {
+  if (address.script) {
     // For the redeem script hash in outputs:
-    this.watch(address.getScriptHash());
+    this.watch(address.getScriptHash160());
     // For the redeem script in inputs:
     this.watch(address.getScript());
   }
 
+  if (address.program) {
+    // For programs inside P2SH
+    this.watch(address.getProgramHash());
+    // For witness scripthash
+    if (address.script)
+      this.watch(address.getScriptHash256());
+  }
+
   // For the pubkey hash in outputs:
   this.watch(address.getKeyHash());
   // For the pubkey in inputs:
@@ -1274,13 +1282,21 @@ Pool.prototype.watchAddress = function watchAddress(address) {
 };
 
 Pool.prototype.unwatchAddress = function unwatchAddress(address) {
-  if (address.type === 'scripthash') {
+  if (addres.script) {
     // For the redeem script hash in p2sh outputs:
-    this.unwatch(address.getScriptHash());
+    this.unwatch(address.getScriptHash160());
     // For the redeem script in p2sh inputs:
     this.unwatch(address.getScript());
   }
 
+  if (address.program) {
+    // For programs inside P2SH
+    this.unwatch(address.getProgramHash());
+    // For witness scripthash
+    if (address.script)
+      this.unwatch(address.getScriptHash256());
+  }
+
   // For the pubkey hash in p2pk/multisig outputs:
   this.unwatch(address.getKeyHash());
   // For the pubkey in p2pkh inputs:
diff --git a/lib/bcoin/protocol/framer.js b/lib/bcoin/protocol/framer.js
index c84ade76..12cc936a 100644
--- a/lib/bcoin/protocol/framer.js
+++ b/lib/bcoin/protocol/framer.js
@@ -583,10 +583,16 @@ Framer._block = function _block(block, witness) {
   var off = 0;
   var txSize = 0;
   var txs = [];
+  var hasWitness;
   var i, tx, p;
 
   for (i = 0; i < block.txs.length; i++) {
-    tx = witness && block.txs[i].hasWitness()
+    if (witness) {
+      hasWitness = block.txs[i].hasWitness
+        ? block.txs[i].hasWitness()
+        : block.txs[i]._witness;
+    }
+    tx = hasWitness
       ? Framer.witnessTX(block.txs[i])
       : Framer.tx(block.txs[i]);
     txs.push(tx);
diff --git a/lib/bcoin/script.js b/lib/bcoin/script.js
index eb7bbab9..ce36b23e 100644
--- a/lib/bcoin/script.js
+++ b/lib/bcoin/script.js
@@ -206,18 +206,19 @@ script.encode = function encode(s) {
 // Witnesses aren't scripts, but we still
 // want to convert [0] to OP_0, [0xff] to 1negate, etc.
 script.decodeWitness = function decodeWitness(witness) {
-  var chunk, i, op;
   var script = [];
+  var chunk, i;
 
   for (i = 0; i < witness.length; i++) {
     chunk = witness[i];
-    op = chunk;
 
-    if (chunk.length === 1) {
-      if (chunk[0] === 0xff)
-        op = '1negate';
-      else if (chunk[0] >= 0 && chunk <= 16)
+    if (chunk.length <= 1) {
+      if (chunk.length === 0)
+        op = new Buffer([]);
+      else if (chunk[0] >= 1 && chunk <= 16)
         op = chunk[0];
+      else if (chunk[0] === 0xff)
+        op = '1negate';
     }
 
     script.push(op);
@@ -227,20 +228,22 @@ script.decodeWitness = function decodeWitness(witness) {
 };
 
 script.encodeWitness = function encodeWitness(script) {
-  var chunk, i, chunk;
   var witness = [];
+  var chunk, i;
 
   for (i = 0; i < script.length; i++) {
     chunk = script[i];
 
-    if (chunk === '1negate')
+    if (chunk === 0)
+      chunk = new Buffer([]);
+    else if (chunk >= 1 && chunk <= 16)
+      chunk = new Buffer([chunk]);
+    else if (chunk === '1negate')
       chunk = new Buffer([0xff]);
-    else if (chunk >= 0 && chunk <= 16)
-      chunk = new Buffer([op]);
 
-    assert(Buffer.isBuffer(op));
+    assert(Buffer.isBuffer(chunk));
 
-    witness.push(op);
+    witness.push(chunk);
   }
 
   return witness;
@@ -455,29 +458,24 @@ script.verifyProgram = function verifyProgram(witness, output, tx, i, flags) {
   }
 
   for (j = 0; j < stack.length; j++) {
-    if (stack[j].length > constants.script.maxSize) {
-      throw new Eror('max size');
+    if (stack[j].length > constants.script.maxSize)
       return false;
-    }
   }
 
-  utils.print(script.format(stack));
+  utils.debug(bcoin.script.format(stack));
+  utils.debug(bcoin.script.format(redeem));
 
   res = script.execute(redeem, stack, tx, i, flags);
 
-  utils.print(script.format(redeem));
-  utils.print(script.format(stack));
+  utils.debug(bcoin.script.format(stack));
+
   // Verify the script did not fail as well as the stack values
-  if (!res || stack.length === 0 || !script.bool(stack.pop())) {
-    throw new Error('script failed');
+  if (!res || stack.length === 0 || !script.bool(stack.pop()))
     return false;
-  }
 
   // Witnesses always require cleanstack
-  if (stack.length !== 0) {
-    throw new Error('cleanstack');
+  if (stack.length !== 0)
     return false;
-  }
 
   return true;
 };
@@ -1135,6 +1133,10 @@ script.execute = function execute(data, stack, tx, index, flags, recurse) {
         }
 
         res = succ >= m;
+
+        if (!res)
+          utils.debug('checkmultisig failed: succ: %d, m: %d', succ, m);
+
         if (o === 'checkmultisigverify') {
           if (!res)
             return false;
@@ -2246,6 +2248,13 @@ script.isDummy = function isDummy(data) {
   return data.length === 0;
 };
 
+script.isZero = function isZero(data) {
+  if (data === 0)
+    return true;
+
+  return script.isDummy(data);
+};
+
 script.isData = function isData(data) {
   if (!Buffer.isBuffer(data))
     return false;
@@ -2492,70 +2501,31 @@ script.isPushOnly = function isPushOnly(s) {
 
 script.getSigops = function getSigops(s, accurate) {
   var i, op;
-  var n = 0;
+  var total = 0;
   var lastOp = -1;
 
   for (i = 0; i < s.length; i++) {
     op = s[i];
+
     if (Buffer.isBuffer(op))
       continue;
+
     if (constants.opcodes[op] == null)
       return 0;
+
     if (op === 'checksig' || op === 'checksigverify') {
-      n++;
+      total++;
     } else if (op === 'checkmultisig' || op === 'checkmultisigverify') {
-      if (accurate && lastOp >= 1 && lastOp <= 16) {
-        n += lastOp;
-      } else {
-        n += constants.script.maxPubkeysPerMultisig;
-      }
+      if (accurate && lastOp >= 1 && lastOp <= 16)
+        total += lastOp;
+      else
+        total += constants.script.maxPubkeysPerMultisig;
     }
+
     lastOp = op;
   }
 
-  return n;
-};
-
-script.getScripthashSigops = function getScripthashSigops(s, prev) {
-  if (prev) {
-    if (!script.isScripthash(prev))
-      return 0;
-  } else {
-    if (!script.isScripthashInput(s))
-      return 0;
-  }
-
-  if (!script.isPushOnly(s))
-    return 0;
-
-  s = script.getRedeem(s);
-
-  // Need to do this too
-  // if (script.isWitnessProgram(s)) {
-  //   call witness sigops
-  // }
-
-  return script.getSigops(s, true);
-};
-
-script.getWitnessSigops = function getWitnessSigops(s) {
-  if (script.isWitnessPubkeyhash(s))
-    return 1;
-  return 0;
-};
-
-script.getWitnessScripthashSigops = function getWitnessScripthashSigops(witness, prev) {
-  var redeem;
-
-  if (!prev)
-    return 0;
-
-  if (!script.isWitnessScripthash(prev))
-    return 0;
-
-  redeem = script.getRedeem(witness);
-
-  return script.getSigops(s, true);
+  return total;
 };
 
 script.getArgs = function getArgs(s) {
@@ -2581,5 +2551,11 @@ script.getArgs = function getArgs(s) {
   if (script.isNulldata(s))
     return -1;
 
+  if (script.isWitnessScripthash(s))
+    return 1;
+
+  if (script.isWitnessPubkeyhash(s))
+    return 2;
+
   return -1;
 };
diff --git a/lib/bcoin/tx.js b/lib/bcoin/tx.js
index 9e24aa48..00bcf874 100644
--- a/lib/bcoin/tx.js
+++ b/lib/bcoin/tx.js
@@ -93,6 +93,7 @@ TX.prototype.clone = function clone() {
   delete tx._witness;
   delete tx._raw;
   delete tx._size;
+  delete tx._offset;
   delete tx._cost;
   delete tx._hash;
   delete tx._whash;
@@ -120,7 +121,6 @@ TX.prototype.witnessHash = function witnessHash(enc) {
       : new Buffer(constants.zeroHash);
   }
 
-  // if (!this._witness)
   if (!this.hasWitness())
     return this.hash(enc);
 
@@ -160,9 +160,13 @@ TX.prototype.renderWitness = function renderWitness() {
   if (this._raw) {
     if (this._witness)
       return this._raw;
+    // We probably shouldn't even render it
+    // as a witness tx if it doesn't have a witness.
     return bcoin.protocol.framer.witnessTX(this);
   }
 
+  // We probably shouldn't even render it
+  // as a witness tx if it doesn't have a witness.
   if (!this.hasWitness())
     return bcoin.protocol.framer.witnessTX(this);
 
@@ -526,37 +530,68 @@ TX.prototype.isFinal = function isFinal(height, ts) {
 };
 
 TX.prototype.getSigops = function getSigops(scriptHash, accurate) {
-  var n = 0;
+  var total = 0;
+
   this.inputs.forEach(function(input) {
     var prev;
-    n += bcoin.script.getSigops(input.script, accurate);
+
+    if (!input.output)
+      return;
+
+    prev = input.output.script;
+
+    total += bcoin.script.getSigops(input.script, accurate);
+
     if (scriptHash && !this.isCoinbase()) {
-      prev = input.output ? input.output.script : null;
-      n += bcoin.script.getScripthashSigops(input.script, prev);
+      if (!bcoin.script.isScripthash(prev))
+        return;
+
+      if (!bcoin.script.isPushOnly(input.script))
+        return;
+
+      prev = bcoin.script.getRedeem(input.script);
+
+      total += bcoin.script.getSigops(prev, true);
     }
   }, this);
+
   this.outputs.forEach(function(output) {
-    n += bcoin.script.getSigops(output.script, accurate);
+    total += bcoin.script.getSigops(output.script, accurate);
   }, this);
-  return n;
+
+  return total;
 };
 
 TX.prototype.getSigopsCost = function getSigopsCost(scriptHash, accurate) {
-  var n = 0;
+  var cost = this.getSigops(scriptHash, accurate) * 4;
+
   this.inputs.forEach(function(input) {
     var prev;
-    n += bcoin.script.getSigops(input.script, accurate) * 4;
-    if (scriptHash && !this.isCoinbase()) {
-      prev = input.output ? input.output.script : null;
-      n += bcoin.script.getScripthashSigops(input.script, prev) * 4;
+
+    if (!input.output)
+      return;
+
+    prev = input.output.script;
+
+    if (bcoin.script.isScripthash(prev))
+      prev = bcoin.script.getRedeem(input.script);
+
+    if (bcoin.script.isWitnessScripthash(prev)) {
+      prev = bcoin.script.getRedeem(input.witness);
+      cost += bcoin.script.getSigops(prev, true);
+    } else {
+      cost += 0;
     }
-    n += bcoin.script.getWitnessScripthashSigops(input.witness, prev);
   }, this);
+
   this.outputs.forEach(function(output) {
-    n += bcoin.script.getSigops(output.script, accurate) * 4;
-    n += bcoin.script.getWitnessSigops(output.script);
+    if (bcoin.script.isWitnessPubkeyhash(output.script))
+      cost += 1;
+    else
+      cost += 0;
   }, this);
-  return n;
+
+  return cost;
 };
 
 TX.prototype.isStandard = function isStandard(flags) {
@@ -639,8 +674,16 @@ TX.prototype.isStandardInputs = function isStandardInputs(flags) {
 
     stack = [];
 
+    // Bitcoind doesn't do this, but it's possible someone
+    // could DoS us by sending ridiculous txs to the mempool
+    // if we don't put this here.
+    if (!bcoin.script.isPushOnly(input.script))
+      return false;
+
     res = bcoin.script.execute(input.script, stack, this, i, flags);
 
+    // TODO: Segwit here.
+
     if (!res)
       return false;
 
@@ -649,15 +692,17 @@ TX.prototype.isStandardInputs = function isStandardInputs(flags) {
       if (stack.length === 0)
         return false;
 
-      redeem = bcoin.script.getRedeem(stack);
+      redeem = stack.pop();
 
-      if (!redeem)
+      if (!Buffer.isBuffer(redeem))
         return false;
 
       // Not accurate?
-      if (bcoin.script.getSize(redeem) > 520)
+      if (redeem.length > 520)
         return false;
 
+      redeem = bcoin.script.decode(redeem);
+
       // Also consider scripthash "unknown"?
       if (bcoin.script.getType(redeem) === 'unknown') {
         if (bcoin.script.getSigops(redeem, true) > maxSigops)
diff --git a/lib/bcoin/utils.js b/lib/bcoin/utils.js
index 8b790a77..6d7bca13 100644
--- a/lib/bcoin/utils.js
+++ b/lib/bcoin/utils.js
@@ -1667,3 +1667,17 @@ utils.checkMerkleBranch = function checkMerkleBranch(hash, branch, index) {
 
   return hash;
 };
+
+utils.indexOf = function indexOf(arr, buf) {
+  var i;
+
+  assert(Array.isArray(arr));
+  assert(Buffer.isBuffer(buf));
+
+  for (i = 0; i < arr.length; i++) {
+    if (utils.isEqual(arr[i], buf))
+      return i;
+  }
+
+  return -1;
+};
diff --git a/lib/bcoin/wallet.js b/lib/bcoin/wallet.js
index d4d8e72f..f91bb0fe 100644
--- a/lib/bcoin/wallet.js
+++ b/lib/bcoin/wallet.js
@@ -51,6 +51,7 @@ function Wallet(options) {
   this.labelMap = {};
   this.change = [];
   this.receive = [];
+  this.program = options.program || false;
 
   this.accountIndex = options.accountIndex || 0;
   this.receiveDepth = options.receiveDepth || 1;
@@ -70,10 +71,6 @@ function Wallet(options) {
     this.type = 'multisig';
 
   assert(this.type === 'pubkeyhash' || this.type === 'multisig');
-  this.prefixType = this.type === 'multisig' ? 'scripthash' : 'pubkeyhash';
-
-  if (network.address.prefixes[this.prefixType] == null)
-    throw new Error('Unknown prefix: ' + this.prefixType);
 
   if (this.m < 1 || this.m > this.n)
     throw new Error('m ranges between 1 and n');
@@ -360,6 +357,7 @@ Wallet.prototype.deriveAddress = function deriveAddress(change, index) {
     index: data.index,
     path: data.path,
     type: this.type,
+    program: this.program,
     m: this.m,
     n: this.n,
     keys: [],
@@ -376,9 +374,12 @@ Wallet.prototype.deriveAddress = function deriveAddress(change, index) {
 
   this.addressMap[address.getKeyAddress()] = data.path;
 
-  if (this.prefixType === 'scripthash')
+  if (this.type === 'multisig')
     this.addressMap[address.getScriptAddress()] = data.path;
 
+  if (this.program)
+    this.addressMap[address.getProgramAddress()] = data.path;
+
   this.emit('add address', address);
 
   return address;
@@ -467,10 +468,30 @@ Wallet.prototype.getScriptHash = function getScriptHash() {
   return this.receiveAddress.getScriptHash();
 };
 
+Wallet.prototype.getScriptHash160 = function getScriptHash160() {
+  return this.receiveAddress.getScriptHash160();
+};
+
+Wallet.prototype.getScriptHash256 = function getScriptHash256() {
+  return this.receiveAddress.getScriptHash160();
+};
+
 Wallet.prototype.getScriptAddress = function getScriptAddress() {
   return this.receiveAddress.getScriptAddress();
 };
 
+Wallet.prototype.getProgram = function getProgram() {
+  return this.receiveAddress.getProgram();
+};
+
+Wallet.prototype.getProgramHash = function getProgramHash() {
+  return this.receiveAddress.getProgramHash();
+};
+
+Wallet.prototype.getProgramAddress = function getProgramAddress() {
+  return this.receiveAddress.getProgramAddress();
+};
+
 Wallet.prototype.getPublicKey = function getPublicKey(enc) {
   return this.receiveAddress.getPublicKey(enc);
 };
@@ -851,6 +872,7 @@ Wallet.prototype.toJSON = function toJSON(noPool) {
     type: this.type,
     m: this.m,
     n: this.n,
+    program: this.program,
     derivation: this.derivation,
     copayBIP45: this.copayBIP45,
     accountIndex: this.accountIndex,
@@ -882,6 +904,7 @@ Wallet._fromJSON = function _fromJSON(json, passphrase) {
     type: json.type,
     m: json.m,
     n: json.n,
+    program: json.program,
     derivation: json.derivation,
     copayBIP45: json.copayBIP45,
     accountIndex: json.accountIndex,
diff --git a/test/wallet-test.js b/test/wallet-test.js
index ee4592b2..2030ecfb 100644
--- a/test/wallet-test.js
+++ b/test/wallet-test.js
@@ -38,14 +38,21 @@ describe('Wallet', function() {
     assert(!bcoin.address.validate('1KQ1wMNwXHUYj1nv2xzsRcKUH8gVFpTFUc'));
   });
 
-  it('should sign/verify TX', function() {
-    var w = bcoin.wallet();
+  function p2pkh(program, bullshitNesting) {
+    var flags = bcoin.protocol.constants.flags.STANDARD_VERIFY_FLAGS;
+
+    if (program)
+      flags |= bcoin.protocol.constants.flags.VERIFY_WITNESS;
+
+    var w = bcoin.wallet({ program: program });
 
     // Input transcation
     var src = bcoin.mtx({
       outputs: [{
         value: 5460 * 2,
-        address: w.getAddress()
+        address: bullshitNesting
+          ? w.getProgramAddress()
+          : w.getAddress()
       }, {
         value: 5460 * 2,
         address: bcoin.address.compileData(new Buffer([]))
@@ -61,7 +68,19 @@ describe('Wallet', function() {
       .addOutput(w.getAddress(), 5460);
 
     w.sign(tx);
-    assert(tx.verify());
+    assert(tx.verify(null, true, flags));
+  }
+
+  it('should sign/verify pubkeyhash tx', function() {
+    p2pkh(false, false);
+  });
+
+  it('should sign/verify witnesspubkeyhash tx', function() {
+    p2pkh(true, false);
+  });
+
+  it('should sign/verify witnesspubkeyhash tx with bullshit nesting', function() {
+    p2pkh(true, true);
   });
 
   it('should multisign/verify TX', function() {
@@ -269,9 +288,15 @@ describe('Wallet', function() {
     cb();
   });
 
-  it('should verify 2-of-3 p2sh tx', function(cb) {
+  function multisig(program, bullshitNesting, cb) {
+    var flags = bcoin.protocol.constants.flags.STANDARD_VERIFY_FLAGS;
+
+    if (program)
+      flags |= bcoin.protocol.constants.flags.VERIFY_WITNESS;
+
     // Create 3 2-of-3 wallets with our pubkeys as "shared keys"
     var w1 = bcoin.wallet({
+      program: program,
       derivation: 'bip44',
       type: 'multisig',
       m: 2,
@@ -279,6 +304,7 @@ describe('Wallet', function() {
     });
 
     var w2 = bcoin.wallet({
+      program: program,
       derivation: 'bip44',
       type: 'multisig',
       m: 2,
@@ -286,6 +312,7 @@ describe('Wallet', function() {
     });
 
     var w3 = bcoin.wallet({
+      program: program,
       derivation: 'bip44',
       type: 'multisig',
       m: 2,
@@ -309,11 +336,22 @@ describe('Wallet', function() {
     assert.equal(w2.getAddress(), addr);
     assert.equal(w3.getAddress(), addr);
 
+    var paddr = w1.getProgramAddress();
+    assert.equal(w1.getProgramAddress(), paddr);
+    assert.equal(w2.getProgramAddress(), paddr);
+    assert.equal(w3.getProgramAddress(), paddr);
+
     // Add a shared unspent transaction to our wallets
     var utx = bcoin.mtx();
-    utx.addOutput({ address: addr, value: 5460 * 10 });
+    if (bullshitNesting)
+      utx.addOutput({ address: paddr, value: 5460 * 10 });
+    else
+      utx.addOutput({ address: addr, value: 5460 * 10 });
+
     utx.addInput(dummyInput);
 
+    assert(w1.ownOutput(utx.outputs[0]));
+
     // Simulate a confirmation
     utx.ps = 0;
     utx.ts = 1;
@@ -337,17 +375,15 @@ describe('Wallet', function() {
     // Create a tx requiring 2 signatures
     var send = bcoin.mtx();
     send.addOutput({ address: receive.getAddress(), value: 5460 });
-    assert(!send.verify());
+    assert(!send.verify(null, true, flags));
     var result = w1.fill(send, { m: w1.m, n: w1.n });
     assert(result);
     w1.sign(send);
 
-    // console.log(bcoin.script.format(send.inputs[0]));
-
-    assert(!send.verify());
+    assert(!send.verify(null, true, flags));
     w2.sign(send);
 
-    assert(send.verify());
+    assert(send.verify(null, true, flags));
 
     assert.equal(w1.changeDepth, 1);
     var change = w1.changeAddress.getAddress();
@@ -374,8 +410,12 @@ describe('Wallet', function() {
     assert.equal(w2.changeAddress.getAddress(), change);
     assert.equal(w3.changeAddress.getAddress(), change);
 
-    send.inputs[0].script[2] = 0;
-    assert(!send.verify(null, true));
+    if (program)
+      send.inputs[0].witness[2] = new Buffer([]);
+    else
+      send.inputs[0].script[2] = 0;
+
+    assert(!send.verify(null, true, flags));
     assert.equal(send.getFee().toNumber(), 10000);
 
     w3 = bcoin.wallet.fromJSON(w3.toJSON());
@@ -385,6 +425,18 @@ describe('Wallet', function() {
     assert.equal(w3.changeAddress.getAddress(), change);
 
     cb();
+  }
+
+  it('should verify 2-of-3 scripthash tx', function(cb) {
+    multisig(false, false, cb);
+  });
+
+  it('should verify 2-of-3 witnessscripthash tx', function(cb) {
+    multisig(true, false, cb);
+  });
+
+  it('should verify 2-of-3 witnessscripthash tx with bullshit nesting', function(cb) {
+    multisig(true, true, cb);
   });
 
   var coinbase = '010000000001010000000000000000000000000000000000000000000000000000000000000000ffffffff2c027156266a24aa21a9edb1e139795984903d6629ddedf3763fb9bc582fd68a46b1f8c7c57f9fbcc7fc900101ffffffff02887d102a0100000023210290dd626747729e1cc445cb9a11cfb7e78ea896db9f5c335e6730491d9ee7474dac0000000000000000266a24aa21a9edb1e139795984903d6629ddedf3763fb9bc582fd68a46b1f8c7c57f9fbcc7fc900120000000000000000000000000000000000000000000000000000000000000000000000000';
@@ -404,11 +456,8 @@ describe('Wallet', function() {
       }]
     });
     src.addInput(dummyInput);
-    console.log(src.toJSON());
     var t = bcoin.protocol.parser.parseWitnessTX(new Buffer(coinbase, 'hex'));
-    utils.print(t);
     var t = new bcoin.tx(bcoin.protocol.parser.parseWitnessTX(new Buffer(w2pkh, 'hex')));
-    utils.print(t);
     delete t._raw;
     delete t._hash;
     delete t._whash;