diff --git a/masonry-layout/masonry-layout-tests.ts b/masonry-layout/masonry-layout-tests.ts
index 8b13789179..e83a898f54 100644
--- a/masonry-layout/masonry-layout-tests.ts
+++ b/masonry-layout/masonry-layout-tests.ts
@@ -1 +1,48 @@
-
+// test file for masonry-layout.d.ts
+
+/// <reference path="../jquery/jquery.d.ts" />
+/// <reference path="./masonry-layout.d.ts" />
+
+//import {Masonry} from "./masonry-layout.d.ts";
+
+// responsive layouts
+function testResponsiveLayouts() {
+    $('.grid').masonry({
+        itemSelector: '.grid-item',
+        columnWidth: '.grid-sizer',
+        percentPosition: true
+    });
+}
+
+// recommended Options
+function testRecommendedOptions() {
+    $('.grid').masonry({
+        columnWidth: 200,
+        itemSelector: '.grid-item'
+    });
+
+    var msnry = new Masonry.Masonry('.grid', {
+        columnWidth: 200,
+        itemSelector: '.grid-item'
+    });
+}
+
+// extended Options
+function testExtendedOptions() {
+    var msnry = new Masonry.Masonry('.grid', {
+        itemSelector: '.grid-item',
+        columnWidth: '.grid-sizer',
+        percentPosition: true,
+        gutter: '.gutter-sizer',
+        stamp: '.stamp',
+        fitWidth: true,
+        originLeft: true,
+        originTop: true,
+        containerStyle: {
+            position: 'relative'
+        },
+        transitionDuration: '0.4s',
+        resize: true,
+        initLayout: true
+    }); 
+} 
diff --git a/masonry-layout/masonry-layout.d.ts b/masonry-layout/masonry-layout.d.ts
new file mode 100644
index 0000000000..0923a8f463
--- /dev/null
+++ b/masonry-layout/masonry-layout.d.ts
@@ -0,0 +1,70 @@
+// Type definitions for Masonry 4.0.0 
+// Project: https://github.com/desandro/masonry 
+// Definitions by: Mark Wilson <https://github.com/m-a-wilson>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped 
+
+/// <reference path="../jquery/jquery.d.ts" /> 
+
+// Modified from original definitions by: 
+// Travis Brown < https://github.com/warriorrocker>
+
+declare module Masonry {
+
+     class Masonry implements MasonryGrid { 
+        constructor(options?: MasonryOptions); 
+        constructor(selector: string, options?: MasonryOptions); 
+    } 
+
+     interface MasonryGrid {
+        masonry?(): void;
+        masonry?(eventName: string, listener: any): void;
+
+        // layout 
+        layout?(): void;
+        layoutItems?(items: Array<any>, isStill?: boolean): void;
+        stamp?(elements: Array<any>): void;
+        unstamp?(elements: Array<any>): void;
+
+        // add and remove items 
+        appended?(elements: Array<any>): void;
+        prepended?(elements: Array<any>): void;
+        addItems?(elements: Array<any>): void;
+        remove?(elements: Array<any>): void;
+
+        // events 
+        on?(eventName: string, listener: any): void;
+        off?(eventName: string, listener: any): void;
+        once?(eventName: string, listener: any): void;
+
+        // utilities 
+        reloadItems?(): void;
+        destroy?(): void;
+        getItemElements?(): Array<any>;
+        data?(element: Element): Masonry;
+    }
+
+     interface MasonryOptions {
+
+        // layout 
+        itemSelector?: string;
+        columnWidth?: any;
+        percentPosition?: boolean;
+        gutter?: any;
+        stamp?: string;
+        fitWidth?: boolean;
+        originLeft?: boolean;
+        originTop?: boolean;
+
+        // setup 
+        containerStyle?: Object;
+        transitionDuration?: any;
+        resize?: boolean;
+        initLayout?: boolean;
+    }
+}
+
+interface JQuery {
+	masonry(options?: Masonry.MasonryOptions): JQuery;
+}
+
+