diff --git a/index.html b/index.html
index 0d6943e..846886f 100644
--- a/index.html
+++ b/index.html
@@ -13,7 +13,6 @@
         }
 
         svg {
-            border:10px solid dodgerblue;
             width:940px;
         }
 
@@ -24,37 +23,66 @@
             width:960px;
         }
 
-        .slider {
+        .range-container {
+            display:inline-block;
+            height:100%;
+            text-align:right;
+            vertical-align:top;
+            width:25%;
+        }
+
+        .range-container input {
+            height:50px;
+            width:80%;
+        }
 
+        .comment-container {
+            background:khaki;
+            display:inline-block;
+            height:100%;
+            vertical-align:top;
+            width:50%;
+        }
+
+        .msg {
+            font-size:13px;
+            font-weight:bold;
+            line-height:30px;
         }
 
         .top {
-            background:#f88;
+
         }
 
         .bottom {
-            background:#4e0;
             height:100px;
         }
 
-        button {
-            border:1px solid #333;
-            background:#888;
-            padding:3px;
+        .controls-container {
+            display:inline-block;
+            height:100%;
+            vertical-align:top;
+            width:25%;
         }
 
-        button.fa {
+        .controls-container button {
+            border:1px solid #fff;
+            background:#d4d4d4;
+            color:#aaa;
             cursor:pointer;
             font-size:12px;
-            height:20px;
-            line-height:14px;
-            margin-right:5px;
-            transition:background 0.2s ease;
-            width:20px;
+            height:30px;
+            line-height:30px;
+            margin:0 5px 10px 0;
+            text-align:center;
+            transition:background 0.2s ease, border 0.2s ease;
+            width:30px;
         }
 
-        button:hover {
-            background:#aaa;
+        .controls-container button:hover {
+            background:#bbb;
+            border:1px solid #aaa;
+            color:#888;
         }
     </style>
 </head>
@@ -67,7 +95,7 @@
     <div class="sorter" data-algorithm='quick'></div>
 
 
-    <h1>Mergesort discussion</h1>
+    <!-- <h1>Mergesort discussion</h1>
     used by firefox and safari. <br>
 
     <div class="sorter" data-algorithm='merge'></div>
@@ -97,7 +125,7 @@
     <h1>radix sort discussion</h1>
 
     <div class="sorter" data-algorithm='radix'></div>
-
+ -->
 <!--
     <h1>Heapsort discussion</h1>
 
@@ -115,6 +143,8 @@
 
     <script type='text/javascript' src='vendor/d3/d3.min.js'></script>
     <script type='text/javascript' src='js/visualizer.js'></script>
+    <script type='text/javascript' src='js/visualizer-actions.js'></script>
+    <script type='text/javascript' src='js/visualizer-inits.js'></script>
     <script type='text/javascript' src='js/sorter.js'></script>
     <script type='text/javascript' src='js/quicksort.js'></script>
     <script type='text/javascript' src='js/mergesort.js'></script>
@@ -126,27 +156,14 @@
 
     <script type='text/javascript'>
         var dump = function(arr) {
-            console.log(arr)
             var d = [];
             arr.forEach(function(obj) {
                 d.push(obj.value);
             })
 
-            // return d.join(',');
+            return d.join(',');
         };
 
-        // var SS = new RadixSort();
-
-        // var data = SS.generate(15);
-        // console.log('DATA: ' + dump(data));
-
-        // var shuffled = SS.shuffle(data);
-        // console.log('SHUFFLED: ' + dump(shuffled));
-
-        // var ordered = Object.create(shuffled);
-        // ordered = SS.sort(ordered, 0, ordered.length - 1);
-        // console.log('ORDERED: ' + dump(ordered));
-
 
     // Wrap anonymous function to avoid polluting global namespace.
     (function() {
@@ -154,8 +171,7 @@
         var V;
         for (key in elements) {
             if (elements.hasOwnProperty(key)) {
-                V = new Visualizer(elements[key]);
-                // V.init();
+                new Visualizer(elements[key]);
             }
         }
     })();
diff --git a/js/bubblesort.js b/js/bubblesort.js
index 0a03cdd..6dd1e3a 100644
--- a/js/bubblesort.js
+++ b/js/bubblesort.js
@@ -27,4 +27,6 @@ BubbleSort.prototype.sort = function(arr) {
     if (swapped === true) {
         this.sort(arr);
     }
+
+    return arr;
 };
diff --git a/js/insertionsort.js b/js/insertionsort.js
index acc7674..60d3ba7 100644
--- a/js/insertionsort.js
+++ b/js/insertionsort.js
@@ -33,4 +33,6 @@ InsertionSort.prototype.sort = function(arr) {
             }
         }
     }
+
+    return arr;
 };
diff --git a/js/quicksort.js b/js/quicksort.js
index 3fb80ac..88d4c46 100644
--- a/js/quicksort.js
+++ b/js/quicksort.js
@@ -3,20 +3,15 @@
  */
 var QuickSort = function() {
     this.instructions = [];
+    this.swaps = 0;
+    this.comparisons = 0;
 };
 
 QuickSort.prototype = Object.create(Sorter.prototype);
 
-/**
- *
- */
-QuickSort.prototype.addInstruction = function(operation, left, right, pivot) {
-    this.instructions.push({
-        operation: operation,
-        left: left,
-        right: right,
-        pivot: pivot
-    });
+QuickSort.prototype.instruct = function() {
+    this.instructions.push(arguments);
+    return this;
 };
 
 // NOTE adds to an instruction set
@@ -25,7 +20,9 @@ QuickSort.prototype.addInstruction = function(operation, left, right, pivot) {
  */
 QuickSort.prototype.sort = function(arr, start, end) {
     if (end - start <= 0) {
-        this.addInstruction('single', start, end, null);
+        this.instruct('highlight', end)
+            .instruct('message1', 'Start: ' + start)
+            .instruct('message2', 'End: ' + end)
         return arr;
     }
 
@@ -36,17 +33,27 @@ QuickSort.prototype.sort = function(arr, start, end) {
     var pivotval = arr[pivot].value;
     var tmp;
 
-    this.addInstruction('init', left, right, pivot);
+    this.instruct('initSection', left, right)
+        .instruct('highlight', pivot)
+        .instruct('message3', 'Pivot value: ' + pivotval);
 
     while (left <= right) {
         while (arr[left].value < pivotval) {
             left++;
-            this.addInstruction('inc-left', left, right, pivot);
+
+            this.comparisons++;
+            this.instruct('marker1', left, 'Left')
+                .instruct('message1', 'Left: ' + left)
+                .instruct('stats1', 'Comparisons: ' + this.comparisons)
         }
 
         while (arr[right].value > pivotval) {
             right--;
-            this.addInstruction('dec-right', left, right, pivot);
+
+            this.comparisons++;
+            this.instruct('marker2', right, 'Right')
+                .instruct('message2', 'Right: ' + right)
+                .instruct('stats1', 'Comparisons: ' + this.comparisons)
         }
 
         if (left <= right) {
@@ -54,11 +61,16 @@ QuickSort.prototype.sort = function(arr, start, end) {
             arr[left] = arr[right];
             arr[right] = tmp;
 
-            this.addInstruction('swap', left, right, pivot);
-
             left++;
             right--;
-            this.addInstruction('swap-inc-dec', left, right, pivot);
+
+            this.swaps++;
+            this.instruct('swap', left, right)
+                .instruct('stats2', 'Swaps: ' + this.swaps)
+                .instruct('message1', 'Left: ' + left)
+                .instruct('message2', 'Right: ' + right)
+                .instruct('marker1', left)
+                .instruct('marker2', right);
         }
     }
 
diff --git a/js/selectionsort.js b/js/selectionsort.js
index 155b231..e876467 100644
--- a/js/selectionsort.js
+++ b/js/selectionsort.js
@@ -11,6 +11,8 @@ SelectionSort.prototype = Object.create(Sorter.prototype);
  *
  */
 SelectionSort.prototype.sort = function(arr) {
+    console.error('selection sort is broken.');
+
     var len = arr.length;
     var i;
     var j;
@@ -37,4 +39,6 @@ SelectionSort.prototype.sort = function(arr) {
     }
 
     // console.info(`swaps: ${swaps}, comparisons: ${comparisons} `);
+
+    return arr;
 };
diff --git a/js/shellsort.js b/js/shellsort.js
index 71445d2..d1b0c28 100644
--- a/js/shellsort.js
+++ b/js/shellsort.js
@@ -21,6 +21,8 @@ ShellSort.prototype.sort = function(arr) {
 
     var IS = new InsertionSort();
     IS.sort(arr);
+
+    return arr;
 };
 
 /**
diff --git a/js/visualizer-actions.js b/js/visualizer-actions.js
new file mode 100644
index 0000000..9b7eb9a
--- /dev/null
+++ b/js/visualizer-actions.js
@@ -0,0 +1,125 @@
+/**
+ * Instructions contain a string with the name of a function in this object which is called to perform an action.
+ */
+Visualizer.prototype.actions = {
+    /**
+     *
+     */
+    initSection: function() {
+        console.warn('INIT SECTION');
+    },
+
+    /**
+     *
+     */
+    swap: function(indexA, indexB) {
+        console.warn('SWAP');
+    // Move up
+    // NOTE Two way binding here between dataset and function parameter?
+    // NOTE swapping will not reorder index and i parameter will be off
+    // NOTE discuss chained transitions: http://bl.ocks.org/mbostock/1125997
+        // this.groups
+        //     .transition().duration(400)
+        //         .attr('transform', function doTransform(d) {
+        //             if (d.index === indexA) {
+        //                 d.index = indexB;
+        //             }
+        //             else if (d.index === indexB) {
+        //                 d.index = indexA;
+        //             }
+
+        //             return `translate(${d.index * (Visualizer.itemW + Visualizer.spacerW)}, ${Visualizer.itemY})`;
+        //         })
+    },
+
+    /**
+     * Highlights an index.
+     */
+    highlight: function(index) {
+        console.warn('HIGHLIGHT');
+    },
+
+    /**
+     * Un-highlights an index.
+     */
+    unhighlight: function(index) {
+        console.warn('UNHIGHLIGHT');
+    },
+
+    // /**
+    //  * Greys out an item.
+    //  */
+    // fade: function(startIndex, endIndex) {
+    //     console.log(`fading from ${startIndex} to ${endIndex}`)
+
+    //     this.svg.selectAll('rect')
+    //         // NOTE this replaces the fill function reference for each rectangle - key point!
+    //         .attr('fill', function fill(d) {
+    //             if (d.index >= startIndex && d.index <= endIndex) {
+    //                 console.log(`${d.index} to ${d.fade}`)
+    //                 return d.fade;
+    //             }
+    //             return d.fill;
+    //         });
+    // };
+
+    // /**
+    //  * Restores all items to un-greyed state.
+    //  */
+    // unfade: function() {
+    //     this.svg.selectAll('rect')
+    //         .attr('fill', function fill(d) {
+    //             console.log(`unfade ${d.index}`)
+    //             return d.fill;
+    //         })
+    // };
+
+    /**
+     * Moves marker 1 to an index and sets its text label.
+     */
+    marker1: function(index, label) {
+        console.warn('MARKER1')
+    },
+
+    /**
+     * Moves marker 2 to an index and sets its text label.
+     */
+    marker2: function(index, label) {
+        console.warn('MARKER2')
+    },
+
+    /**
+     * Updates message in stats 1 div.
+     */
+    stats1: function(message) {
+        console.warn('STATS1')
+    },
+
+    /**
+     * Updates message in stats 2 div.
+     */
+    stats2: function(message) {
+        console.warn('STATS2')
+    },
+
+    /**
+     * Updates message in message 1 div.
+     */
+    message1: function(message) {
+        console.warn('MESSAGE1')
+    },
+
+    /**
+     * Updates message in message 2 div.
+     */
+    message2: function(message) {
+        console.warn('MESSAGE2')
+    },
+
+    /**
+     * Updates message in message 3 div.
+     */
+    message3: function(message) {
+        console.warn('MESSAGE3')
+    },
+};
diff --git a/js/visualizer-inits.js b/js/visualizer-inits.js
new file mode 100644
index 0000000..6a5abc5
--- /dev/null
+++ b/js/visualizer-inits.js
@@ -0,0 +1,132 @@
+/**
+ *
+ */
+Visualizer.prototype.initItems = function(n) {
+    var data = this.sorter.generate(n);
+    var shuffled = this.sorter.shuffle(data);
+    var ordered = Object.create(shuffled);
+    ordered = this.sorter.sort(ordered, 0, ordered.length - 1);
+
+    // A swap on the dataset will not take effect until after transition is complete, so custom index is required.
+    var n = 0;
+    for (i in shuffled) {
+        shuffled[i].index = n++;
+    }
+
+    this.groups = this.svg.selectAll('g').data(shuffled).enter().append('g')
+        .attr('transform', `translate(0, ${Visualizer.itemY})`);
+
+    this.groups.append('rect')
+        .attr('height', Visualizer.itemH)
+        .attr('width', Visualizer.itemW)
+        .attr('fill', function doFill(d) { return `rgb(0, 0, ${d.value})`; });
+
+    this.groups.transition(500)
+        .attr('transform', function doTransform(d, i) {
+            return `translate(${i * (Visualizer.itemW + Visualizer.spacerW)}, ${Visualizer.itemY})`;
+        });
+
+    this.groups.append('text')
+        .text(function t(d) { return d.value; })
+        .attr('fill', '#aaa')
+        .attr('font-size', 10)
+        .attr('font-family', 'sans-serif')
+        .attr('transform', function doTransform(d) {
+            return `rotate(90 0,0), translate(5, -3)`;
+        });
+
+    setTimeout(this.followInstruction.bind(this, 0), 500);
+};
+
+/**
+ *
+ */
+Visualizer.prototype.initComments = function() {
+    var container = document.createElement('div');
+    container.className = 'comment-container';
+
+    var div1 = document.createElement('div');
+    div1.className = 'comment';
+
+    var div2 = document.createElement('div');
+    div2.className = 'comment';
+
+    var div3 = document.createElement('div');
+    div3.className = 'comment';
+
+    container.appendChild(div1);
+    container.appendChild(div2);
+    container.appendChild(div3);
+
+    return container;
+};
+
+/**
+ *
+ */
+Visualizer.prototype.initRange = function() {
+    var container = document.createElement('div');
+    container.className = 'range-container';
+
+    var msg = document.createElement('div');
+    msg.className = 'msg';
+    msg.innerHTML = "Number of items (n) = 10";
+
+    var range = document.createElement('input');
+    range.setAttribute('type', 'range');
+    range.setAttribute('value', 40);
+    range.setAttribute('min', 5);
+    range.setAttribute('max', 80);
+    range.addEventListener('change', this.rangeChange.bind(this));
+    range.addEventListener('input', this.rangeInput.bind(null, msg));
+
+    container.appendChild(range);
+    container.appendChild(msg);
+
+    return container;
+};
+
+/**
+ *
+ */
+Visualizer.prototype.initControls = function() {
+    var play = document.createElement('button');
+    play.className = 'fa fa-play';
+    play.title = 'Play'
+    play.addEventListener('click', onclick);
+
+    var back = document.createElement('button');
+    back.className = 'fa fa-step-backward';
+    back.title = 'Step Backward';
+    back.addEventListener('click', onclick);
+
+    var forward = document.createElement('button');
+    forward.className = 'fa fa-step-forward'
+    forward.title = 'Step Forward';
+    forward.addEventListener('click', onclick);
+
+    var reset = document.createElement('button');
+    reset.className = 'fa fa-fast-backward';
+    reset.title = 'Restart'
+    reset.addEventListener('click', onclick);
+
+    var msg1 = document.createElement('div');
+    msg1.className = 'msg';
+    msg1.innerHTML = 'Swaps: 999';
+
+    var msg2 = document.createElement('div');
+    msg2.className = 'msg';
+    msg2.innerHTML = 'Comparisons: 999';
+
+    var container = document.createElement('div');
+    container.className = 'controls-container';
+
+    container.appendChild(reset);
+    container.appendChild(back);
+    container.appendChild(play);
+    container.appendChild(forward);
+    container.appendChild(msg1);
+    container.appendChild(msg2);
+
+    return container;
+};
diff --git a/js/visualizer.js b/js/visualizer.js
index a6828ae..e9c45fd 100644
--- a/js/visualizer.js
+++ b/js/visualizer.js
@@ -19,6 +19,7 @@ function Visualizer(parent) {
     var range = this.initRange();
     parent.querySelector('.bottom').appendChild(range);
 
+    this.svg = d3.select(parent.querySelector('.top')).append('svg');
     this.groups = null;
     this.parent = parent;
     this.sorter = null;
@@ -59,7 +60,7 @@ function Visualizer(parent) {
     // this.instructions = null;
     // this.currentInstruction = 0;
 
-    this.init(10);
+    this.initItems(10);
 };
 
 // Public static properties (mutable)
@@ -71,185 +72,40 @@ Visualizer.itemY    = 20;
 /**
  *
  */
-Visualizer.prototype.init = function(n) {
-    var data = this.sorter.generate(n);
-    var shuffled = this.sorter.shuffle(data);
-    var ordered = Object.create(shuffled);
-    ordered = this.sorter.sort(ordered, 0, ordered.length - 1);
-
-    // console.log(ordered);
-
-    // var x = []
-    // ordered.forEach(function(obj0) {
-    //     x.push(obj0.value);
-    // })
-
-    // console.log(x.join(','));
-
-    // // A swap on the dataset will not take effect until after transition is complete, so custom index is required.
-    // var n = 0;
-    // for (i in shuffled) {
-    //     shuffled[i].index = n++;
-    // }
-
-    // var svg = d3.select(this.parent.querySelector('.top')).append('svg');
-
-    // this.groups = svg.selectAll('g').data(shuffled).enter().append('g')
-    //     .attr('transform', `translate(0, ${Visualizer.itemY})`);
-
-    // this.groups.append('rect')
-    //     .attr('height', Visualizer.itemH)
-    //     .attr('width', Visualizer.itemW)
-    //     .attr('fill', function doFill(d) { return `rgb(0, 0, ${d.value})`; });
-
-    // this.groups.transition(500)
-    //     .attr('transform', function doTransform(d, i) {
-    //         return `translate(${i * (Visualizer.itemW + Visualizer.spacerW)}, ${Visualizer.itemY})`;
-    //     });
-
-    // this.groups.append('text')
-    //     .text(function t(d) { return d.value; })
-    //     .attr('fill', '#aaa')
-    //     .attr('font-size', 10)
-    //     .attr('font-family', 'sans-serif')
-    //     .attr('transform', function doTransform(d) {
-    //         return `rotate(90 0,0), translate(5, -3)`;
-    //     });
-
-    // setTimeout(this.followInstruction.bind(this, QS.instructions, 0), 500);
-};
-
-/**
- *
- */
-Visualizer.prototype.swap = function(indexA, indexB) {
-    // Move up
-    // NOTE Two way binding here between dataset and function parameter?
-    // NOTE swapping will not reorder index and i parameter will be off
-    // NOTE discuss chained transitions: http://bl.ocks.org/mbostock/1125997
-    this.groups
-        .transition().duration(400)
-            .attr('transform', function doTransform(d) {
-                if (d.index === indexA) {
-                    d.index = indexB;
-                }
-                else if (d.index === indexB) {
-                    d.index = indexA;
-                }
-
-                return `translate(${d.index * (Visualizer.itemW + Visualizer.spacerW)}, ${Visualizer.itemY})`;
-            })
-};
-
-/**
- *
- */
-Visualizer.prototype.fade = function(startIndex, endIndex) {
-    console.log(`fading from ${startIndex} to ${endIndex}`)
-
-    this.svg.selectAll('rect')
-        // NOTE this replaces the fill function reference for each rectangle - key point!
-        .attr('fill', function fill(d) {
-            if (d.index >= startIndex && d.index <= endIndex) {
-                console.log(`${d.index} to ${d.fade}`)
-                return d.fade;
-            }
-            return d.fill;
-        });
-};
-
-/**
- *
- */
-Visualizer.prototype.unfade = function() {
-    this.svg.selectAll('rect')
-        .attr('fill', function fill(d) {
-            console.log(`unfade ${d.index}`)
-            return d.fill;
-        })
-};
-
-/**
- *
- */
-Visualizer.prototype.followInstruction = function(instructions, index) {
-    if (index >= instructions.length) {
+Visualizer.prototype.followInstruction = function(index) {
+    if (index >= this.sorter.instructions.length) {
         return;
     }
 
-    var i = instructions[index];
+    var i = this.sorter.instructions[index];
     console.log(i);
 
-    if (i.operation === 'swap' && i.left < i.right) {
-        this.swap(i.left, i.right);
-        setTimeout(this.followInstruction.bind(this, instructions, index + 1), 400);
-    }
-    else if (i.operation === 'init') {
-        // this.unfade();
-        // this.fade(0, i.left - 1);
-        // this.fade(i.right + 1, 1000)
-        this.followInstruction(instructions, index + 1);
+    // NOTE interesting pattern here
+    if (typeof this.actions[i[0]] === 'function') {
+        this.actions[i[0]](i);
+
+        if (this.actions[i[1]] === true) {
+           setTimeout(this.followInstruction.bind(this, index + 1), 400);
+        }
+        else {
+           this.followInstruction(index + 1);
+        }
     }
-    else if (i.operation === 'swap') {
-        this.followInstruction(instructions, index + 1);
+    // TODO document this
+    else if (this.actions[i[0]] !== undefined) {
+        console.warn(this[i[0]]);
     }
     else {
-        this.followInstruction(instructions, index + 1);
+        console.error(i);
+        throw new Error('Unidentified instruction.');
     }
 };
 
-/**
- *
- */
-Visualizer.prototype.initComments = function() {
-    var container = document.createElement('div');
-    container.className = 'comment-container';
-
-    var div1 = document.createElement('div');
-    div1.className = 'comment';
-
-    var div2 = document.createElement('div');
-    div2.className = 'comment';
-
-    var div3 = document.createElement('div');
-    div3.className = 'comment';
-
-    container.appendChild(div1);
-    container.appendChild(div2);
-    container.appendChild(div3);
-
-    return container;
-};
-
-/**
- *
- */
-Visualizer.prototype.initRange = function() {
-    var container = document.createElement('div');
-    container.className = 'range-container';
-
-    var label = document.createElement('div');
-    label.innerHTML = "n: 40";
-
-    var range = document.createElement('input');
-    range.setAttribute('type', 'range');
-    range.setAttribute('value', 40);
-    range.setAttribute('min', 5);
-    range.setAttribute('max', 80);
-    range.addEventListener('change', this.rangeChange.bind(this));
-    range.addEventListener('input', this.rangeInput.bind(null, label));
-
-    container.appendChild(range);
-    container.appendChild(label);
-
-    return container;
-};
-
 /**
  *
  */
 Visualizer.prototype.rangeInput = function(label, event) {
-    label.innerHTML = 'Items: ' + event.target.value;
+    label.innerHTML = 'Number of items (n) = ' + event.target.value;
 };
 
 /**
@@ -258,38 +114,3 @@ Visualizer.prototype.rangeInput = function(label, event) {
 Visualizer.prototype.rangeChange = function(event) {
     this.init(event.target.value);
 };
-
-/**
- *
- */
-Visualizer.prototype.initControls = function() {
-    var play = document.createElement('button');
-    play.className = 'fa fa-play';
-    play.title = 'Play'
-    play.addEventListener('click', onclick);
-
-    var back = document.createElement('button');
-    back.className = 'fa fa-step-backward';
-    back.title = 'Step Backward';
-    back.addEventListener('click', onclick);
-
-    var forward = document.createElement('button');
-    forward.className = 'fa fa-step-forward'
-    forward.title = 'Step Forward';
-    forward.addEventListener('click', onclick);
-
-    var reset = document.createElement('button');
-    reset.className = 'fa fa-fast-backward';
-    reset.title = 'Restart'
-    reset.addEventListener('click', onclick);
-
-    var container = document.createElement('div');
-    container.className = 'controls-container';
-
-    container.appendChild(reset);
-    container.appendChild(back);
-    container.appendChild(play);
-    container.appendChild(forward);
-
-    return container;
-};