diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
index f39e1f53d..a204feb3c 100644
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -84,6 +84,7 @@ All definitions files include a header with the author and editors, so at some p
 * [fs-extra](https://github.com/jprichardson/node-fs-extra) (by [midknight41](https://github.com/midknight41))
 * [FullCalendar](http://arshaw.com/fullcalendar/) (by [Neil Stalker](https://github.com/nestalk))
 * [Gamepad](http://www.w3.org/TR/gamepad/) (by [Kon](http://phyzkit.net/))
+* [GeoJSON](http://geojson.org/) (by [Jake Bruun](https://github.com/cobster))
 * [Giraffe](https://github.com/barc/backbone.giraffe) (by [Matt McCray](https://github.com/darthapo))
 * [glDatePicker](http://glad.github.com/glDatePicker/) (by [Dániel Tar](https://github.com/qcz))
 * [Glob](https://github.com/isaacs/node-glob) (by [vvakame](https://github.com/vvakame))
diff --git a/geojson/geojson-tests.ts b/geojson/geojson-tests.ts
new file mode 100644
index 000000000..ed953520b
--- /dev/null
+++ b/geojson/geojson-tests.ts
@@ -0,0 +1,129 @@
+/// <reference path="./geojson.d.ts" />
+
+var featureCollection: GeoJSON.FeatureCollection =  { 
+    type: "FeatureCollection",
+    features: [   
+        { 
+            type: "Feature",
+            geometry: {
+                type: "Point", 
+                coordinates: [102.0, 0.5]
+            },
+            properties: {
+                prop0: "value0"
+            }
+        },
+        { 
+            type: "Feature",
+            geometry: {
+                type: "LineString",
+                coordinates: [
+                    [102.0, 0.0], 
+                    [103.0, 1.0], 
+                    [104.0, 0.0], 
+                    [105.0, 1.0]
+                ]
+            },
+            properties: {
+                prop0: "value0",
+                prop1: 0.0
+            }
+        },
+        { 
+            type: "Feature",
+            geometry: {
+                type: "Polygon",
+                coordinates: [
+                    [ [100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0] ]
+                ]
+            },
+            properties: {
+                prop0: "value0",
+                prop1: {
+                    that: "this"
+                }
+            }
+        }
+    ],
+    crs: {
+        type: "link",
+        properties: {
+            href: "http://example.com/crs/42",
+            type: "proj4"
+        }
+    }
+}
+
+var feature: GeoJSON.Feature = { 
+    type: "Feature",
+    bbox: [-180.0, -90.0, 180.0, 90.0],
+    geometry: {
+        type: "Polygon",
+        coordinates: [
+            [[-180.0, 10.0], [20.0, 90.0], [180.0, -5.0], [-30.0, -90.0]]
+        ]
+    },
+    properties: null
+};
+
+
+var point: GeoJSON.Point = { 
+	type: "Point",
+	coordinates: [100.0, 0.0]
+};
+
+var lineString: GeoJSON.LineString = {
+	type: "LineString",
+	coordinates: [ [100.0, 0.0], [101.0, 1.0] ]
+};
+
+var polygon: GeoJSON.Polygon = { 
+    type: "Polygon",
+    coordinates: [
+        [ [100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0] ]
+    ]
+};
+
+var polygonWithHole: GeoJSON.Polygon = { 
+    type: "Polygon",
+    coordinates: [
+        [ [100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0] ],
+        [ [100.2, 0.2], [100.8, 0.2], [100.8, 0.8], [100.2, 0.8], [100.2, 0.2] ]
+    ]
+};
+
+var multiPoint: GeoJSON.MultiPoint = {
+    type: "MultiPoint",
+    coordinates: [ [100.0, 0.0], [101.0, 1.0] ]
+};
+
+var multiLineString: GeoJSON.MultiLineString = { 
+    type: "MultiLineString",
+    coordinates: [
+        [ [100.0, 0.0], [101.0, 1.0] ],
+        [ [102.0, 2.0], [103.0, 3.0] ]
+    ]
+};
+
+var multiPolygon: GeoJSON.MultiPolygon = { 
+    type: "MultiPolygon",
+    coordinates: [
+        [[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]],
+        [[[100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0]],
+         [[100.2, 0.2], [100.8, 0.2], [100.8, 0.8], [100.2, 0.8], [100.2, 0.2]]]
+    ]
+}
+
+var geometryCollection: GeoJSON.GeometryCollection = { 
+    type: "GeometryCollection",
+    "geometries": [
+        { 
+            type: "Point",
+            coordinates: [100.0, 0.0]
+        },
+        { 
+            type: "LineString",
+            coordinates: [ [101.0, 0.0], [102.0, 1.0] ]
+        }
+    ]
+}
\ No newline at end of file
diff --git a/geojson/geojson.d.ts b/geojson/geojson.d.ts
new file mode 100644
index 000000000..1f8a23db5
--- /dev/null
+++ b/geojson/geojson.d.ts
@@ -0,0 +1,127 @@
+// Type definitions for GeoJSON Format Specification
+// Project: http://geojson.org/
+// Definitions by: Jacob Bruun <https://github.com/cobster/>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
+declare module GeoJSON {
+
+    /***
+    * http://geojson.org/geojson-spec.html#geojson-objects
+    */
+    export interface GeoJsonObject
+    {
+        type: string;
+        bbox?: number[];
+        crs?: CoordinateReferenceSystem;
+    }
+        
+    /***
+    * http://geojson.org/geojson-spec.html#positions
+    */
+    export interface Position
+    {
+        [index: number]: number;
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#geometry-objects
+    */
+    export interface GeometryObject extends GeoJsonObject
+    {
+        coordinates: any
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#point
+    */
+    export interface Point extends GeometryObject
+    {
+        coordinates: Position
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#multipoint
+    */
+    export interface MultiPoint extends GeometryObject
+    {
+    
+        coordinates: Position[]
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#linestring
+    */
+    export interface LineString extends GeometryObject
+    {
+        coordinates: Position[]
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#multilinestring
+    */
+    export interface MultiLineString extends GeometryObject
+    {
+        coordinates: Position[][]
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#polygon
+    */
+    export interface Polygon extends GeometryObject
+    {
+        coordinates: Position[][]
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#multipolygon
+    */
+    export interface MultiPolygon extends GeometryObject
+    {
+        coordinates: Position[][][]
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#geometry-collection
+    */
+    export interface GeometryCollection extends GeoJsonObject
+    {
+        geometries: GeometryObject[];
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#feature-objects
+    */
+    export interface Feature extends GeoJsonObject
+    {
+        geometry: GeometryObject;
+        properties: any;
+        id?: string;
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#feature-collection-objects
+    */
+    export interface FeatureCollection extends GeoJsonObject
+    {
+        features: Feature[];
+    }
+
+    /***
+    * http://geojson.org/geojson-spec.html#coordinate-reference-system-objects
+    */
+    export interface CoordinateReferenceSystem 
+    {
+        type: string;
+        properties: any;
+    }
+	
+    export interface NamedCoordinateReferenceSystem extends CoordinateReferenceSystem
+    {
+        properties: { name: string }
+    }
+
+    export interface LinkedCoordinateReferenceSystem extends CoordinateReferenceSystem
+    {
+        properties: { href: string; type: string }
+    }
+}
\ No newline at end of file