diff --git a/Script.js b/Script.js
index 4e89d9e..9df0d6f 100644
--- a/Script.js
+++ b/Script.js
@@ -122,6 +122,47 @@ function spec(b) {
 	    this.chunks[this.chunks.length-1] == OP_CHECKMULTISIG);
   };
 
+  Script.prototype.finishedMultiSig = function()
+  {
+    var nsigs = 0;
+    for (var i = 0; i < this.chunks.length-1; i++)
+      if (this.chunks[i] !== 0)
+        nsigs++;
+
+    var serializedScript = this.chunks[this.chunks.length-1];
+    var script = new Script(serializedScript);
+    var nreq = script.chunks[0] - 80; //see OP_2-OP_16
+
+    if (nsigs == nreq)
+      return true;
+    else
+      return false;
+  }
+
+  Script.prototype.removePlaceHolders = function()
+  {
+    var chunks = [];
+    for (var i in this.chunks)
+    {
+      var chunk = this.chunks[i];
+      if (chunk != 0)
+        chunks.push(chunk);
+    }
+    this.chunks = chunks;
+    this.updateBuffer();
+    return this;
+  }
+
+  Script.prototype.prependOp0 = function()
+  {
+    var chunks = [0];
+    for (i in this.chunks)
+      chunks.push(this.chunks[i]);
+    this.chunks = chunks;
+    this.updateBuffer();
+    return this;
+  }
+
   // is this a script form we know?
   Script.prototype.classify = function ()
   {
diff --git a/test/Script.js b/test/Script.js
new file mode 100644
index 0000000..98597c7
--- /dev/null
+++ b/test/Script.js
@@ -0,0 +1,55 @@
+var assert = require('assert');
+var Script = require('../Script').class();
+var networks = require('../networks');
+
+describe('Script', function(){
+  describe('#finishedMultiSig', function(){
+    it('should report that this scriptSig has finished being signed', function() {
+      var scriptHex = '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';
+      //decoded: 0 3046022100954d2aa7af9a2de34b04e4151842933df81acc379580cd0c057883cfb0994a8b022100de1530692eda9cdb567c94e05fc856cfbc26fcf3482148bde85f143032f4902501 3045022100d164d174118497d93e0062b573be78d4b9417aee09889cd242a966af73367917022054f095be0bce9edee556a2216239fcad45a7a64d8fb318dc5375c9159724689a01 5221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae
+      //meaning: OP_0 sig sig serialized_script
+      var scriptBuf = new Buffer(scriptHex, 'hex');
+      var script = new Script(scriptBuf);
+      assert.equal(script.finishedMultiSig(), true);
+    });
+    it('should report that this scripSig has not finished being signed', function() {
+      var scriptHex = '483045022002da7fae9b98615115b7e9a4f1d9efd581463b670f91ec6404a14cb6fc9c4531022100ff449d72ba4e72deb4317267e2d38cec9fd2f58a9afa39c9f5e35f5678694ff50100004c695221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae';
+      //decoded: 3045022002da7fae9b98615115b7e9a4f1d9efd581463b670f91ec6404a14cb6fc9c4531022100ff449d72ba4e72deb4317267e2d38cec9fd2f58a9afa39c9f5e35f5678694ff501 0 0 5221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae
+      //meaning: sig place_holder place_holder serialized_script
+      var scriptBuf = new Buffer(scriptHex, 'hex');
+      var script = new Script(scriptBuf);
+      assert.equal(script.finishedMultiSig(), false);
+    });
+  });
+
+  describe('#removePlaceHolders', function(){
+    it('should remove place holders from this script', function(){
+      var scriptHex = '483045022002da7fae9b98615115b7e9a4f1d9efd581463b670f91ec6404a14cb6fc9c4531022100ff449d72ba4e72deb4317267e2d38cec9fd2f58a9afa39c9f5e35f5678694ff50100004c695221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae';
+      //decoded: 3045022002da7fae9b98615115b7e9a4f1d9efd581463b670f91ec6404a14cb6fc9c4531022100ff449d72ba4e72deb4317267e2d38cec9fd2f58a9afa39c9f5e35f5678694ff501 0 0 5221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae
+      //meaning: sig place_holder place_holder serialized_script
+      var scriptBuf = new Buffer(scriptHex, 'hex');
+      var script = new Script(scriptBuf);
+      script.removePlaceHolders();
+
+      var scriptHex2 = '483045022002da7fae9b98615115b7e9a4f1d9efd581463b670f91ec6404a14cb6fc9c4531022100ff449d72ba4e72deb4317267e2d38cec9fd2f58a9afa39c9f5e35f5678694ff5014c695221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae';
+      //decoded: 3045022002da7fae9b98615115b7e9a4f1d9efd581463b670f91ec6404a14cb6fc9c4531022100ff449d72ba4e72deb4317267e2d38cec9fd2f58a9afa39c9f5e35f5678694ff501 5221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae
+      //meaning: sig serialized_script
+      var scriptBuf2 = new Buffer(scriptHex2, 'hex');
+      var script2 = new Script(scriptBuf2);
+
+      assert.equal(script.buffer.toString('hex'), script2.buffer.toString('hex'));
+    });
+  });
+
+  describe('prependOp0', function() {
+    it('should prepend the script with OP_0', function() {
+      var scriptHex = '483045022002da7fae9b98615115b7e9a4f1d9efd581463b670f91ec6404a14cb6fc9c4531022100ff449d72ba4e72deb4317267e2d38cec9fd2f58a9afa39c9f5e35f5678694ff50100004c695221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae';
+      //decoded: 3045022002da7fae9b98615115b7e9a4f1d9efd581463b670f91ec6404a14cb6fc9c4531022100ff449d72ba4e72deb4317267e2d38cec9fd2f58a9afa39c9f5e35f5678694ff501 0 0 5221033e4cc6b6ee8d8ce3335fed6d4917b2bbbac0f5743b2ced101ba036f95c51e59421023147410ce15e0a31c2bb970cdf01517266dc2c9182f5938636ed363cfd4cc3ae210342a3c8a4b20c7a122a011a07063df04e4c5ad520a1302a2a66e174fd9b0d4ea453ae
+      //meaning: sig place_holder place_holder serialized_script
+      var scriptBuf = new Buffer(scriptHex, 'hex');
+      var script = new Script(scriptBuf);
+      script.prependOp0();
+      assert.equal(script.chunks[0], 0);
+    });
+  });
+});