diff --git a/src/vs/workbench/electron-browser/main.ts b/src/vs/workbench/electron-browser/main.ts
index 3a9b7e9cd7bd598c4c731b573a284548a1f11d5c..f1b566e63dab8a5a23522f9f4c462f2796bc2010 100644
--- a/src/vs/workbench/electron-browser/main.ts
+++ b/src/vs/workbench/electron-browser/main.ts
@@ -112,9 +112,12 @@ function openWorkbench(configuration: IWindowConfiguration): TPromise<void> {
 
 function createAndInitializeWorkspaceService(configuration: IWindowConfiguration, environmentService: EnvironmentService, workspacesService: IWorkspacesService): TPromise<WorkspaceService> {
 	return validateWorkspacePath(configuration).then(() => {
-		const workspaceConfigPath = configuration.workspace ? uri.file(configuration.workspace.configPath) : null;
-		const folderPath = configuration.folderPath ? uri.file(configuration.folderPath) : null;
-		const workspaceService = (workspaceConfigPath || configuration.folderPath) ? new WorkspaceServiceImpl(workspaceConfigPath, folderPath, environmentService, workspacesService) : new EmptyWorkspaceServiceImpl(environmentService);
+		let workspaceService: WorkspaceServiceImpl | EmptyWorkspaceServiceImpl;
+		if (configuration.workspace || configuration.folderPath) {
+			workspaceService = new WorkspaceServiceImpl(configuration.workspace || configuration.folderPath, environmentService, workspacesService);
+		} else {
+			workspaceService = new EmptyWorkspaceServiceImpl(environmentService);
+		}
 
 		return workspaceService.initialize().then(() => workspaceService, error => new EmptyWorkspaceServiceImpl(environmentService));
 	});
diff --git a/src/vs/workbench/services/configuration/common/configurationModels.ts b/src/vs/workbench/services/configuration/common/configurationModels.ts
index 9a0226735f8d8ab22b9eb94d3dd987603940fefd..74c1d65e249692ccc831df7a8c4a3aa5fe983518 100644
--- a/src/vs/workbench/services/configuration/common/configurationModels.ts
+++ b/src/vs/workbench/services/configuration/common/configurationModels.ts
@@ -29,10 +29,6 @@ export class WorkspaceConfigurationModel<T> extends CustomConfigurationModel<T>
 		this._workspaceConfiguration = this.consolidate();
 	}
 
-	get id(): string {
-		return this._raw['id'];
-	}
-
 	get folders(): URI[] {
 		return this._folders;
 	}
diff --git a/src/vs/workbench/services/configuration/node/configuration.ts b/src/vs/workbench/services/configuration/node/configuration.ts
index ef2d4e4313b2308db182163a59bbb669a10b71a7..d9779ee22193c66e7475aaa4fe5f891669f0dbbd 100644
--- a/src/vs/workbench/services/configuration/node/configuration.ts
+++ b/src/vs/workbench/services/configuration/node/configuration.ts
@@ -33,7 +33,7 @@ import { Registry } from 'vs/platform/registry/common/platform';
 import { ExtensionsRegistry, ExtensionMessageCollector } from 'vs/platform/extensions/common/extensionsRegistry';
 import { IConfigurationNode, IConfigurationRegistry, Extensions, editorConfigurationSchemaId, IDefaultConfigurationExtension, validateProperty, ConfigurationScope, schemaId } from 'vs/platform/configuration/common/configurationRegistry';
 import { createHash } from 'crypto';
-import { getWorkspaceLabel, IWorkspacesService } from 'vs/platform/workspaces/common/workspaces';
+import { getWorkspaceLabel, IWorkspacesService, IWorkspaceIdentifier, ISingleFolderWorkspaceIdentifier, isSingleFolderWorkspaceIdentifier } from 'vs/platform/workspaces/common/workspaces';
 
 interface IStat {
 	resource: URI;
@@ -338,12 +338,21 @@ export class WorkspaceServiceImpl extends WorkspaceService {
 
 	public _serviceBrand: any;
 
+	private workspaceConfigPath: URI;
+	private folderPath: URI;
 	private baseConfigurationService: GlobalConfigurationService<any>;
 	private workspaceConfiguration: WorkspaceConfiguration;
 	private cachedFolderConfigs: StrictResourceMap<FolderConfiguration<any>>;
 
-	constructor(private workspaceConfigPath: URI, private folderPath: URI, private environmentService: IEnvironmentService, private workspacesService: IWorkspacesService, private workspaceSettingsRootFolder: string = WORKSPACE_CONFIG_FOLDER_DEFAULT_NAME) {
+	constructor(private workspaceIdentifier: IWorkspaceIdentifier | ISingleFolderWorkspaceIdentifier, private environmentService: IEnvironmentService, private workspacesService: IWorkspacesService, private workspaceSettingsRootFolder: string = WORKSPACE_CONFIG_FOLDER_DEFAULT_NAME) {
 		super();
+
+		if (isSingleFolderWorkspaceIdentifier(workspaceIdentifier)) {
+			this.folderPath = URI.file(workspaceIdentifier);
+		} else {
+			this.workspaceConfigPath = URI.file(workspaceIdentifier.configPath);
+		}
+
 		this.workspaceConfiguration = this._register(new WorkspaceConfiguration());
 		this.baseConfigurationService = this._register(new GlobalConfigurationService(environmentService));
 	}
@@ -435,11 +444,12 @@ export class WorkspaceServiceImpl extends WorkspaceService {
 		return this.workspaceConfiguration.load(this.workspaceConfigPath)
 			.then(() => {
 				const workspaceConfigurationModel = this.workspaceConfiguration.workspaceConfigurationModel;
-				if (!workspaceConfigurationModel.id || !workspaceConfigurationModel.folders.length) {
+				if (!workspaceConfigurationModel.folders.length) {
 					return TPromise.wrapError<void>(new Error('Invalid workspace configuraton file ' + this.workspaceConfigPath));
 				}
-				const workspaceName = getWorkspaceLabel({ id: workspaceConfigurationModel.id, configPath: this.workspaceConfigPath.fsPath }, this.environmentService);
-				this.workspace = new Workspace(workspaceConfigurationModel.id, workspaceName, workspaceConfigurationModel.folders, this.workspaceConfigPath);
+				const workspaceId = (this.workspaceIdentifier as IWorkspaceIdentifier).id;
+				const workspaceName = getWorkspaceLabel({ id: workspaceId, configPath: this.workspaceConfigPath.fsPath }, this.environmentService);
+				this.workspace = new Workspace(workspaceId, workspaceName, workspaceConfigurationModel.folders, this.workspaceConfigPath);
 				this.legacyWorkspace = new LegacyWorkspace(this.workspace.roots[0]);
 				this._register(this.workspaceConfiguration.onDidUpdateConfiguration(() => this.onWorkspaceConfigurationChanged()));
 				return null;
diff --git a/src/vs/workbench/services/configuration/test/node/configuration.test.ts b/src/vs/workbench/services/configuration/test/node/configuration.test.ts
index aba215904febf67871d070ac9fc489378effdcfb..1ee691bae5f690aa6751a182b448b98da71db558 100644
--- a/src/vs/workbench/services/configuration/test/node/configuration.test.ts
+++ b/src/vs/workbench/services/configuration/test/node/configuration.test.ts
@@ -47,7 +47,7 @@ suite('WorkspaceConfigurationService - Node', () => {
 
 	function createService(workspaceDir: string, globalSettingsFile: string): TPromise<WorkspaceService> {
 		const environmentService = new SettingsTestEnvironmentService(parseArgs(process.argv), process.execPath, globalSettingsFile);
-		const service = new WorkspaceServiceImpl(null, URI.file(workspaceDir), environmentService, null);
+		const service = new WorkspaceServiceImpl(workspaceDir, environmentService, null);
 
 		return service.initialize().then(() => service);
 	}
diff --git a/src/vs/workbench/services/configuration/test/node/configurationEditingService.test.ts b/src/vs/workbench/services/configuration/test/node/configurationEditingService.test.ts
index 7224039236d59c532a18ea96cba4012040ee4fc3..b5c9099cde40eb9375e995744f815f78953be859 100644
--- a/src/vs/workbench/services/configuration/test/node/configurationEditingService.test.ts
+++ b/src/vs/workbench/services/configuration/test/node/configurationEditingService.test.ts
@@ -11,7 +11,6 @@ import os = require('os');
 import path = require('path');
 import fs = require('fs');
 import * as json from 'vs/base/common/json';
-import URI from 'vs/base/common/uri';
 import { TPromise } from 'vs/base/common/winjs.base';
 import { Registry } from 'vs/platform/registry/common/platform';
 import { ParsedArgs, IEnvironmentService } from 'vs/platform/environment/common/environment';
@@ -118,7 +117,7 @@ suite('ConfigurationEditingService', () => {
 		const environmentService = new SettingsTestEnvironmentService(parseArgs(process.argv), process.execPath, globalSettingsFile);
 		instantiationService.stub(IEnvironmentService, environmentService);
 		const workspacesService = instantiationService.stub(IWorkspacesService, {});
-		const workspaceService = noWorkspace ? new EmptyWorkspaceServiceImpl(environmentService) : new WorkspaceServiceImpl(null, URI.file(workspaceDir), environmentService, workspacesService);
+		const workspaceService = noWorkspace ? new EmptyWorkspaceServiceImpl(environmentService) : new WorkspaceServiceImpl(workspaceDir, environmentService, workspacesService);
 		instantiationService.stub(IWorkspaceContextService, workspaceService);
 		instantiationService.stub(IConfigurationService, workspaceService);
 		instantiationService.stub(ILifecycleService, new TestLifecycleService());