diff --git a/src/vs/workbench/api/node/extHostApiCommands.ts b/src/vs/workbench/api/node/extHostApiCommands.ts
index 9a397bc7233..7eb6e84e197 100644
--- a/src/vs/workbench/api/node/extHostApiCommands.ts
+++ b/src/vs/workbench/api/node/extHostApiCommands.ts
@@ -47,6 +47,14 @@ export class ExtHostApiCommands {
 			],
 			returns: 'A promise that resolves to an array of Location-instances.'
 		});
+		this._register('vscode.executeDeclarationProvider', this._executeDeclaraionProvider, {
+			description: 'Execute all declaration provider.',
+			args: [
+				{ name: 'uri', description: 'Uri of a text document', constraint: URI },
+				{ name: 'position', description: 'Position of a symbol', constraint: types.Position }
+			],
+			returns: 'A promise that resolves to an array of Location-instances.'
+		});
 		this._register('vscode.executeTypeDefinitionProvider', this._executeTypeDefinitionProvider, {
 			description: 'Execute all type definition providers.',
 			args: [
@@ -292,6 +300,15 @@ export class ExtHostApiCommands {
 			.then(tryMapWith(typeConverters.location.to));
 	}
 
+	private _executeDeclaraionProvider(resource: URI, position: types.Position): Thenable<types.Location[]> {
+		const args = {
+			resource,
+			position: position && typeConverters.Position.from(position)
+		};
+		return this._commands.executeCommand<modes.Location[]>('_executeDeclarationProvider', args)
+			.then(tryMapWith(typeConverters.location.to));
+	}
+
 	private _executeTypeDefinitionProvider(resource: URI, position: types.Position): Thenable<types.Location[]> {
 		const args = {
 			resource,
diff --git a/src/vs/workbench/test/electron-browser/api/extHostApiCommands.test.ts b/src/vs/workbench/test/electron-browser/api/extHostApiCommands.test.ts
index 8dfcbd3d4c4..863ca25a002 100644
--- a/src/vs/workbench/test/electron-browser/api/extHostApiCommands.test.ts
+++ b/src/vs/workbench/test/electron-browser/api/extHostApiCommands.test.ts
@@ -247,6 +247,36 @@ suite('ExtHostLanguageFeatureCommands', function () {
 		});
 	});
 
+	// --- declaration
+
+	test('Declaration, back and forth', function () {
+
+		disposables.push(extHost.registerDeclarationProvider(nullExtensionDescription, defaultSelector, <vscode.DeclarationProvider>{
+			provideDeclaration(doc: any): any {
+				return new types.Location(doc.uri, new types.Range(0, 0, 0, 0));
+			}
+		}));
+		disposables.push(extHost.registerDeclarationProvider(nullExtensionDescription, defaultSelector, <vscode.DeclarationProvider>{
+			provideDeclaration(doc: any): any {
+				return [
+					new types.Location(doc.uri, new types.Range(0, 0, 0, 0)),
+					new types.Location(doc.uri, new types.Range(0, 0, 0, 0)),
+					new types.Location(doc.uri, new types.Range(0, 0, 0, 0)),
+				];
+			}
+		}));
+
+		return rpcProtocol.sync().then(() => {
+			return commands.executeCommand<vscode.Location[]>('vscode.executeDeclarationProvider', model.uri, new types.Position(0, 0)).then(values => {
+				assert.equal(values.length, 4);
+				for (let v of values) {
+					assert.ok(v.uri instanceof URI);
+					assert.ok(v.range instanceof types.Range);
+				}
+			});
+		});
+	});
+
 	// --- type definition
 
 	test('Type Definition, invalid arguments', function () {