diff --git a/README.md b/README.md
index 30c81dd14..214494c3e 100755
--- a/README.md
+++ b/README.md
@@ -287,6 +287,7 @@ List of Definitions
 * [WinJS](http://msdn.microsoft.com/en-us/library/windows/apps/br229773.aspx) (from TypeScript samples)
 * [WinRT](http://msdn.microsoft.com/en-us/library/windows/apps/br211377.aspx) (from TypeScript samples)
 * [ws](http://einaros.github.io/ws/) (by [Paul Loyd](https://github.com/loyd))
+* [XRegExp](http://xregexp.com/) (by [Bart van der Schoor](https://github.com/Bartvds))
 * [YouTube](https://developers.google.com/youtube/) (by [Daz Wilkin](https://github.com/DazWilkin/))
 * [YouTube Analytics API](https://developers.google.com/youtube/analytics/) (by [Frank M](https://github.com/sgtfrankieboy))
 * [YouTube Data API](https://developers.google.com/youtube/v3/) (by [Frank M](https://github.com/sgtfrankieboy/))
diff --git a/xregexp/xregexp-tests.ts b/xregexp/xregexp-tests.ts
new file mode 100644
index 000000000..62d37439e
--- /dev/null
+++ b/xregexp/xregexp-tests.ts
@@ -0,0 +1,134 @@
+/// <reference path="xregexp.d.ts" />
+
+import X = require('xregexp');
+import XRegExp = X.XRegExp;
+import TokenOpts = X.TokenOpts;
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+var exp: RegExp;
+var expArr: RegExp[];
+var chain: RegExp[];
+var regex: RegExp;
+var value: any;
+var str: string;
+var scope: string;
+var search: string;
+var searchEx: RegExp;
+var bool: boolean;
+var strArr: string[];
+var pattern: string;
+var flags: string;
+var right: string;
+var left: string;
+var sticky: boolean;
+var pos: number;
+var num: number;
+var limit: number;
+var obj: Object;
+var matchArr: RegExpExecArray;
+var options: TokenOpts;
+var replacer: Function;
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+regex = XRegExp(str);
+regex = XRegExp(str, flags);
+regex = XRegExp(regex);
+
+str =  XRegExp.version;
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+XRegExp.addToken(regex, (arr, scope) => {
+	matchArr = arr;
+	str = scope;
+	return str;
+});
+
+XRegExp.addToken(regex, (arr, scope) => {
+	matchArr = arr;
+	str = scope;
+	return str;
+}, options);
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+regex = XRegExp.build(pattern, strArr, flags);
+regex = XRegExp.build(pattern, strArr);
+regex = XRegExp.cache(pattern);
+regex = XRegExp.cache(pattern, flags);
+
+str = XRegExp.escape(str);
+
+matchArr = XRegExp.exec(str, regex, pos, sticky);
+matchArr = XRegExp.exec(str, regex, pos);
+matchArr = XRegExp.exec(str, regex);
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+matchArr = XRegExp.forEach(str, regex, (match, index, input, regexp) => {
+	exp = regexp;
+	str = input;
+	num = index;
+	matchArr = match;
+}, obj);
+
+matchArr = XRegExp.forEach(str, regex, (match, index, input, regexp) => {
+	exp = regexp;
+	str = input;
+	num = index;
+	matchArr = match;
+});
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+regex = XRegExp.globalize(regex);
+
+XRegExp.install(str);
+XRegExp.install(obj);
+
+bool = XRegExp.isInstalled(str);
+bool = XRegExp.isRegExp(value);
+strArr = XRegExp.matchChain(str, chain);
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+strArr = XRegExp.matchRecursive(str, left, right, flags, options);
+strArr = XRegExp.matchRecursive(str, left, right, flags);
+strArr = XRegExp.matchRecursive(str, left, right);
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+str = XRegExp.replace(str, search, str, scope);
+str = XRegExp.replace(str, search, str);
+str = XRegExp.replace(str, search, replacer, scope);
+str = XRegExp.replace(str, search, replacer);
+
+str = XRegExp.replace(str, searchEx, str, scope);
+str = XRegExp.replace(str, searchEx, str);
+str = XRegExp.replace(str, searchEx, replacer, scope);
+str = XRegExp.replace(str, searchEx, replacer);
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+strArr = XRegExp.split(str, search, limit);
+strArr = XRegExp.split(str, search);
+strArr = XRegExp.split(str, searchEx, limit);
+strArr = XRegExp.split(str, searchEx);
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+bool = XRegExp.test(str, regex, pos, bool);
+bool = XRegExp.test(str, regex, pos);
+bool = XRegExp.test(str, regex);
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
+XRegExp.uninstall(obj);
+XRegExp.uninstall(str);
+
+regex = XRegExp.union(strArr, flags);
+regex = XRegExp.union(strArr);
+
+// --  --  --  --  --  --  --  --  --  --  --  --  --
+
diff --git a/xregexp/xregexp.d.ts b/xregexp/xregexp.d.ts
new file mode 100644
index 000000000..9e30a2d07
--- /dev/null
+++ b/xregexp/xregexp.d.ts
@@ -0,0 +1,62 @@
+// Type definitions for XRegExp 2.0.0
+// Project: http://xregexp.com
+// Definitions by: Bart van der Schoor <https://github.com/Bartvds>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
+declare module 'xregexp' {
+	// scopes: 'default', 'class', or 'all'
+	/*
+	 Native flags:
+	 g - global
+	 i - ignore case
+	 m - multiline anchors
+	 y - sticky (Firefox 3+)
+	 Additional XRegExp flags:
+	 n - explicit capture
+	 s - dot matches all (aka singleline)
+	 x - free-spacing and line comments (aka extended)
+	 */
+	export interface TokenOpts {
+		scope?: string;
+		trigger?: () => boolean;
+		customFlags?: string;
+	}
+
+	export function XRegExp(pattern: string, flags?: string): RegExp;
+	export function XRegExp(pattern: RegExp): RegExp;
+
+	export module XRegExp {
+		function addToken(regex: RegExp, handler: (matchArr: RegExpExecArray, scope: string) => string, options?: TokenOpts): void;
+
+		function build(pattern: string, subs: string[], flags?: string): RegExp;
+		function cache(pattern: string, flags?: string): RegExp;
+		function escape(str: string): string;
+		function exec(str: string, regex: RegExp, pos?: number, sticky?: boolean): RegExpExecArray;
+		function forEach(str: string, regex: RegExp, callback: (matchArr: RegExpExecArray, index: number, input: string, regexp: RegExp) => void, context?: Object): any;
+		function globalize(regex: RegExp): RegExp;
+
+		function install(options: string): void;
+		function install(options: Object): void;
+
+		function isInstalled(feature: string): boolean;
+		function isRegExp(value: any): boolean;
+		function matchChain(str: string, chain: RegExp[]): string[];
+		function matchRecursive(str: string, left: string, right: string, flags?: string, options?: Object): string[];
+
+		function replace(str: string, search: string, replacement: string, scope?: string): string;
+		function replace(str: string, search: string, replacement: Function, scope?: string): string;
+		function replace(str: string, search: RegExp, replacement: string, scope?: string): string;
+		function replace(str: string, search: RegExp, replacement: Function, scope?: string): string;
+
+		function split(str: string, separator: string, limit?: number): string[];
+		function split(str: string, separator: RegExp, limit?: number): string[];
+
+		function test(str: string, regex: RegExp, pos?: number, sticky?: boolean): boolean;
+
+		function uninstall(options: Object): void;
+		function uninstall(options: string): void;
+
+		function union(patterns: string[], flags?: string): RegExp;
+		var version: string;
+	}
+}