diff --git a/src/interactiveLayer.js b/src/interactiveLayer.js
index 758f816..0ac07be 100644
--- a/src/interactiveLayer.js
+++ b/src/interactiveLayer.js
@@ -7,6 +7,7 @@ the rectangle. The dispatch is given one object which contains the mouseX/Y loca
 It also has 'pointXValue', which is the conversion of mouseX to the x-axis scale.
 */
 nv.interactiveGuideline = function() {
+	"use strict";
 	var tooltip = nv.models.tooltip();
 	//Public settings
 	var width = null
@@ -25,7 +26,7 @@ nv.interactiveGuideline = function() {
 
 	//Private variables
 	var previousXCoordinate = null
-	isMSIE = navigator.userAgent.indexOf("MSIE") !== -1  //Check user-agent for Microsoft Internet Explorer.
+	var isMSIE = navigator.userAgent.indexOf("MSIE") !== -1  //Check user-agent for Microsoft Internet Explorer.
 	;
 
 
@@ -196,6 +197,7 @@ Has the following known issues:
    * Won't work if there are duplicate x coordinate values.
 */
 nv.interactiveBisect = function (values, searchVal, xAccessor) {
+	  "use strict";
       if (! values instanceof Array) return null;
       if (typeof xAccessor !== 'function') xAccessor = function(d,i) { return d.x;}
 
diff --git a/src/models/axis.js b/src/models/axis.js
index 7e749bb..8b29b15 100644
--- a/src/models/axis.js
+++ b/src/models/axis.js
@@ -1,5 +1,5 @@
 nv.models.axis = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/boilerplate.js b/src/models/boilerplate.js
index b7effc4..5b02a4a 100644
--- a/src/models/boilerplate.js
+++ b/src/models/boilerplate.js
@@ -1,6 +1,6 @@
 
 nv.models.chartName = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/bullet.js b/src/models/bullet.js
index 466a309..f39f3ee 100644
--- a/src/models/bullet.js
+++ b/src/models/bullet.js
@@ -4,7 +4,7 @@
 // http://projects.instantcognition.com/protovis/bulletchart/
 
 nv.models.bullet = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/bulletChart.js b/src/models/bulletChart.js
index 220fd72..b7ad60f 100644
--- a/src/models/bulletChart.js
+++ b/src/models/bulletChart.js
@@ -3,7 +3,7 @@
 // based on the work of Clint Ivy, Jamie Love, and Jason Davies.
 // http://projects.instantcognition.com/protovis/bulletchart/
 nv.models.bulletChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/cumulativeLineChart.js b/src/models/cumulativeLineChart.js
index 148047b..747dcb6 100644
--- a/src/models/cumulativeLineChart.js
+++ b/src/models/cumulativeLineChart.js
@@ -1,6 +1,6 @@
 
 nv.models.cumulativeLineChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/discreteBar.js b/src/models/discreteBar.js
index 8bcd56e..65b20f4 100644
--- a/src/models/discreteBar.js
+++ b/src/models/discreteBar.js
@@ -1,6 +1,6 @@
 //TODO: consider deprecating by adding necessary features to multiBar model
 nv.models.discreteBar = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/discreteBarChart.js b/src/models/discreteBarChart.js
index f81213a..685757d 100644
--- a/src/models/discreteBarChart.js
+++ b/src/models/discreteBarChart.js
@@ -1,6 +1,6 @@
 
 nv.models.discreteBarChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/distribution.js b/src/models/distribution.js
index 37b071b..5b2e775 100644
--- a/src/models/distribution.js
+++ b/src/models/distribution.js
@@ -1,6 +1,6 @@
 
 nv.models.distribution = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/historicalBar.js b/src/models/historicalBar.js
index cf23a7a..4429fcd 100644
--- a/src/models/historicalBar.js
+++ b/src/models/historicalBar.js
@@ -1,6 +1,6 @@
 //TODO: consider deprecating and using multibar with single series for this
 nv.models.historicalBar = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/historicalBarChart.js b/src/models/historicalBarChart.js
index bd8058d..85c6723 100644
--- a/src/models/historicalBarChart.js
+++ b/src/models/historicalBarChart.js
@@ -1,6 +1,6 @@
 
 nv.models.historicalBarChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/indentedTree.js b/src/models/indentedTree.js
index 546540c..f9a7d0f 100644
--- a/src/models/indentedTree.js
+++ b/src/models/indentedTree.js
@@ -1,5 +1,5 @@
 nv.models.indentedTree = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/legend.js b/src/models/legend.js
index 3a3c4a2..1886764 100644
--- a/src/models/legend.js
+++ b/src/models/legend.js
@@ -1,5 +1,5 @@
 nv.models.legend = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
@@ -131,7 +131,7 @@ nv.models.legend = function() {
           columnWidths = [];
           seriesPerRow--;
 
-          for (k = 0; k < seriesWidths.length; k++) {
+          for (var k = 0; k < seriesWidths.length; k++) {
             if (seriesWidths[k] > (columnWidths[k % seriesPerRow] || 0) )
               columnWidths[k % seriesPerRow] = seriesWidths[k];
           }
diff --git a/src/models/line.js b/src/models/line.js
index 916a86e..7394d62 100644
--- a/src/models/line.js
+++ b/src/models/line.js
@@ -1,6 +1,6 @@
 
 nv.models.line = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/lineChart.js b/src/models/lineChart.js
index 9c191a8..5f5cd07 100644
--- a/src/models/lineChart.js
+++ b/src/models/lineChart.js
@@ -1,6 +1,6 @@
 
 nv.models.lineChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/linePlusBarChart.js b/src/models/linePlusBarChart.js
index a337a5a..9322e7d 100644
--- a/src/models/linePlusBarChart.js
+++ b/src/models/linePlusBarChart.js
@@ -1,6 +1,6 @@
 
 nv.models.linePlusBarChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/linePlusBarWithFocusChart.js b/src/models/linePlusBarWithFocusChart.js
index 1c7500c..01b21a7 100644
--- a/src/models/linePlusBarWithFocusChart.js
+++ b/src/models/linePlusBarWithFocusChart.js
@@ -1,6 +1,6 @@
 
 nv.models.linePlusBarWithFocusChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/lineWithFisheye.js b/src/models/lineWithFisheye.js
index 94cc593..2739a08 100644
--- a/src/models/lineWithFisheye.js
+++ b/src/models/lineWithFisheye.js
@@ -1,5 +1,6 @@
 
 nv.models.line = function() {
+  "use strict";
   //Default Settings
   var margin = {top: 0, right: 0, bottom: 0, left: 0},
       width = 960,
diff --git a/src/models/lineWithFisheyeChart.js b/src/models/lineWithFisheyeChart.js
index e8846a1..0cfd121 100644
--- a/src/models/lineWithFisheyeChart.js
+++ b/src/models/lineWithFisheyeChart.js
@@ -1,5 +1,6 @@
 
 nv.models.lineChart = function() {
+  "use strict";
   var margin = {top: 30, right: 20, bottom: 50, left: 60},
       color = nv.utils.defaultColor(),
       width = null, 
diff --git a/src/models/lineWithFocusChart.js b/src/models/lineWithFocusChart.js
index 8fab55b..e8c152b 100644
--- a/src/models/lineWithFocusChart.js
+++ b/src/models/lineWithFocusChart.js
@@ -1,6 +1,6 @@
 
 nv.models.lineWithFocusChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
@@ -271,7 +271,7 @@ nv.models.lineWithFocusChart = function() {
           .attr('y', 0)
           .attr('height', availableHeight2);
 
-      gBrush = g.select('.nv-x.nv-brush')
+      var gBrush = g.select('.nv-x.nv-brush')
           .call(brush);
       gBrush.selectAll('rect')
           //.attr('y', -5)
@@ -366,7 +366,7 @@ nv.models.lineWithFocusChart = function() {
 
       function onBrush() {
         brushExtent = brush.empty() ? null : brush.extent();
-        extent = brush.empty() ? x2.domain() : brush.extent();
+        var extent = brush.empty() ? x2.domain() : brush.extent();
 
         //The brush extent cannot be less than one.  If it is, don't update the line chart.
         if (Math.abs(extent[0] - extent[1]) <= 1) {
diff --git a/src/models/multiBar.js b/src/models/multiBar.js
index 858f03c..e5165af 100644
--- a/src/models/multiBar.js
+++ b/src/models/multiBar.js
@@ -1,6 +1,6 @@
 
 nv.models.multiBar = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/multiBarChart.js b/src/models/multiBarChart.js
index 5421c58..6d9cfc4 100644
--- a/src/models/multiBarChart.js
+++ b/src/models/multiBarChart.js
@@ -1,6 +1,6 @@
 
 nv.models.multiBarChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/multiBarHorizontal.js b/src/models/multiBarHorizontal.js
index aff5164..53dbf9c 100644
--- a/src/models/multiBarHorizontal.js
+++ b/src/models/multiBarHorizontal.js
@@ -1,6 +1,6 @@
 
 nv.models.multiBarHorizontal = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/multiBarHorizontalChart.js b/src/models/multiBarHorizontalChart.js
index 57e0c4a..391cdb3 100644
--- a/src/models/multiBarHorizontalChart.js
+++ b/src/models/multiBarHorizontalChart.js
@@ -1,6 +1,6 @@
 
 nv.models.multiBarHorizontalChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/multiBarTimeSeries.js b/src/models/multiBarTimeSeries.js
index 4be3fd9..ca522b5 100644
--- a/src/models/multiBarTimeSeries.js
+++ b/src/models/multiBarTimeSeries.js
@@ -1,5 +1,5 @@
 nv.models.multiBarTimeSeries = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/multiBarTimeSeriesChart.js b/src/models/multiBarTimeSeriesChart.js
index 1c6537c..693f658 100644
--- a/src/models/multiBarTimeSeriesChart.js
+++ b/src/models/multiBarTimeSeriesChart.js
@@ -1,5 +1,5 @@
 nv.models.multiBarTimeSeriesChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/multiChart.js b/src/models/multiChart.js
index 5c6bbd9..351e914 100644
--- a/src/models/multiChart.js
+++ b/src/models/multiChart.js
@@ -1,5 +1,5 @@
 nv.models.multiChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/ohlcBar.js b/src/models/ohlcBar.js
index e34fd46..93b8682 100644
--- a/src/models/ohlcBar.js
+++ b/src/models/ohlcBar.js
@@ -1,6 +1,6 @@
 
 nv.models.ohlcBar = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/parallelCoordinates.js b/src/models/parallelCoordinates.js
index 659af09..d2cbf47 100644
--- a/src/models/parallelCoordinates.js
+++ b/src/models/parallelCoordinates.js
@@ -3,7 +3,7 @@
 // http://bl.ocks.org/jasondavies/1341281
 
 nv.models.parallelCoordinates = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/pie.js b/src/models/pie.js
index 475a78f..d065227 100644
--- a/src/models/pie.js
+++ b/src/models/pie.js
@@ -1,5 +1,5 @@
 nv.models.pie = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/pieChart.js b/src/models/pieChart.js
index 2767181..3c97926 100644
--- a/src/models/pieChart.js
+++ b/src/models/pieChart.js
@@ -1,5 +1,5 @@
 nv.models.pieChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/scatter.js b/src/models/scatter.js
index aa0124c..af710a4 100644
--- a/src/models/scatter.js
+++ b/src/models/scatter.js
@@ -1,6 +1,6 @@
 
 nv.models.scatter = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/scatterChart.js b/src/models/scatterChart.js
index 64dd61e..2ea2a50 100644
--- a/src/models/scatterChart.js
+++ b/src/models/scatterChart.js
@@ -1,6 +1,6 @@
 
 nv.models.scatterChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/scatterPlusLineChart.js b/src/models/scatterPlusLineChart.js
index ad53822..5076062 100644
--- a/src/models/scatterPlusLineChart.js
+++ b/src/models/scatterPlusLineChart.js
@@ -1,6 +1,6 @@
 
 nv.models.scatterPlusLineChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/sparkline.js b/src/models/sparkline.js
index bc23fb1..b3f4cd7 100644
--- a/src/models/sparkline.js
+++ b/src/models/sparkline.js
@@ -1,6 +1,6 @@
 
 nv.models.sparkline = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/sparklinePlus.js b/src/models/sparklinePlus.js
index cb4a14d..c0a0202 100644
--- a/src/models/sparklinePlus.js
+++ b/src/models/sparklinePlus.js
@@ -1,6 +1,6 @@
 
 nv.models.sparklinePlus = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/stackedArea.js b/src/models/stackedArea.js
index 215d9c4..c7406f0 100644
--- a/src/models/stackedArea.js
+++ b/src/models/stackedArea.js
@@ -1,6 +1,6 @@
 
 nv.models.stackedArea = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/models/stackedAreaChart.js b/src/models/stackedAreaChart.js
index 0c5190f..b76fde8 100644
--- a/src/models/stackedAreaChart.js
+++ b/src/models/stackedAreaChart.js
@@ -1,6 +1,6 @@
 
 nv.models.stackedAreaChart = function() {
-
+  "use strict";
   //============================================================
   // Public Variables with Default Settings
   //------------------------------------------------------------
diff --git a/src/tooltip.js b/src/tooltip.js
index 1abd0b3..4df78ec 100644
--- a/src/tooltip.js
+++ b/src/tooltip.js
@@ -5,7 +5,7 @@ window.nv.tooltip.show is the old tooltip code.
 window.nv.tooltip.* also has various helper methods.
 */
 (function() {
-
+  "use strict";
   window.nv.tooltip = {};
 
   /* Model which can be instantiated to handle tooltip rendering.