diff --git a/lodash/lodash-tests.ts b/lodash/lodash-tests.ts
index 28c148e75..3d3eef68d 100644
--- a/lodash/lodash-tests.ts
+++ b/lodash/lodash-tests.ts
@@ -601,6 +601,22 @@ result = <boolean>_.isEmpty([1, 2, 3]);
 result = <boolean>_.isEmpty({});
 result = <boolean>_.isEmpty('');
 
+var moe = { 'name': 'moe', 'age': 40 };
+var copy = { 'name': 'moe', 'age': 40 };
+
+result = <boolean>_.isEqual(moe, copy);
+
+var words = ['hello', 'goodbye'];
+var otherWords = ['hi', 'goodbye'];
+
+result = <boolean>_.isEqual(words, otherWords, function(a, b) {
+  var reGreet = /^(?:hello|hi)$/i,
+      aGreet = _.isString(a) && reGreet.test(a),
+      bGreet = _.isString(b) && reGreet.test(b);
+
+  return (aGreet || bGreet) ? (aGreet == bGreet) : undefined;
+});
+
 
 var mergeNames = {
   'stooges': [
@@ -671,10 +687,7 @@ _.chain([1, 2, 3, 200])
 	.map(function (num: number) { return num * num })
 	.value();
 
-var moe = { name: 'moe', luckyNumbers: [13, 27, 34] };
-var clone = { name: 'moe', luckyNumbers: [13, 27, 34] };
-moe == clone;
-_.isEqual(moe, clone);
+
 
 
 
diff --git a/lodash/lodash.d.ts b/lodash/lodash.d.ts
index 3b3471415..e29003783 100644
--- a/lodash/lodash.d.ts
+++ b/lodash/lodash.d.ts
@@ -2399,6 +2399,23 @@ declare module _ {
 	**/
 	export function isEmpty(value: string): boolean;
 
+	/**
+	* Performs a deep comparison between two values to determine if they are equivalent to each 
+	* other. If a callback is provided it will be executed to compare values. If the callback 
+	* returns undefined comparisons will be handled by the method instead. The callback is bound to 
+	* thisArg and invoked with two arguments; (a, b).
+	* @param a The value to compare.
+	* @param b The other value to compare.
+	* @param callback The function to customize comparing values.
+	* @param thisArg The this binding of callback.
+	* @return True if the values are equivalent, else false.
+	**/
+	export function isEqual(
+		a: any,
+		b: any,
+		callback?: (a, b) => boolean,
+		thisArg?: any): boolean;
+
 	/**
 	* Recursively merges own enumerable properties of the source object(s), that don't resolve 
 	* to undefined into the destination object. Subsequent sources will overwrite property 
@@ -2612,14 +2629,7 @@ declare module _ {
 	**/
 	export function tap<T>(object: T, intercepter: Function): T;
 
-	/**
-	* Performs an optimized deep comparison between the two objects,
-	* to determine if they should be considered equal.
-	* @param object Compare to `other`.
-	* @param other Compare to `object`.
-	* @return True if `object` is equal to `other`.
-	**/
-	export function isEqual(object: any, other: any): boolean;
+