diff --git a/src/vs/workbench/api/browser/mainThreadWorkspace.ts b/src/vs/workbench/api/browser/mainThreadWorkspace.ts
index 062c43408a0..30ebb309289 100644
--- a/src/vs/workbench/api/browser/mainThreadWorkspace.ts
+++ b/src/vs/workbench/api/browser/mainThreadWorkspace.ts
@@ -70,6 +70,7 @@ export class MainThreadWorkspace implements MainThreadWorkspaceShape {
 		this._contextService.onDidChangeWorkspaceFolders(this._onDidChangeWorkspace, this, this._toDispose);
 		this._contextService.onDidChangeWorkbenchState(this._onDidChangeWorkspace, this, this._toDispose);
 		this._workspaceTrustManagementService.onDidChangeTrust(this._onDidGrantWorkspaceTrust, this, this._toDispose);
+		this._workspaceTrustManagementService.onDidChangeTrustedFolders(this._onDidChangeWorkspaceTrustedFolders, this, this._toDispose);
 	}
 
 	dispose(): void {
@@ -251,6 +252,12 @@ export class MainThreadWorkspace implements MainThreadWorkspaceShape {
 		return this._workspaceTrustRequestService.requestWorkspaceTrust(options);
 	}
 
+	async $isResourceTrusted(resource: UriComponents): Promise<boolean> {
+		const uri = URI.revive(resource);
+		const trustInfo = await this._workspaceTrustManagementService.getUriTrustInfo(uri);
+		return trustInfo.trusted;
+	}
+
 	private isWorkspaceTrusted(): boolean {
 		return this._workspaceTrustManagementService.isWorkspaceTrusted();
 	}
@@ -259,6 +266,10 @@ export class MainThreadWorkspace implements MainThreadWorkspaceShape {
 		this._proxy.$onDidGrantWorkspaceTrust();
 	}
 
+	private _onDidChangeWorkspaceTrustedFolders(): void {
+		this._proxy.$onDidChangeWorkspaceTrustedFolders();
+	}
+
 	// --- edit sessions ---
 	private registeredEditSessionProviders = new Map<number, IDisposable>();
 
diff --git a/src/vs/workbench/api/common/extHost.api.impl.ts b/src/vs/workbench/api/common/extHost.api.impl.ts
index 21cb7bb1839..0f9b9ec6e87 100644
--- a/src/vs/workbench/api/common/extHost.api.impl.ts
+++ b/src/vs/workbench/api/common/extHost.api.impl.ts
@@ -1271,6 +1271,14 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 				checkProposedApiEnabled(extension, 'workspaceTrust');
 				return extHostWorkspace.requestWorkspaceTrust(options);
 			},
+			isResourceTrusted: (resource: vscode.Uri) => {
+				checkProposedApiEnabled(extension, 'workspaceTrust');
+				return extHostWorkspace.isResourceTrusted(resource);
+			},
+			onDidChangeWorkspaceTrustedFolders: (listener, thisArgs?, disposables?) => {
+				checkProposedApiEnabled(extension, 'workspaceTrust');
+				return _asExtensionEvent(extHostWorkspace.onDidChangeWorkspaceTrustedFolders)(listener, thisArgs, disposables);
+			},
 			onDidGrantWorkspaceTrust: (listener, thisArgs?, disposables?) => {
 				return _asExtensionEvent(extHostWorkspace.onDidGrantWorkspaceTrust)(listener, thisArgs, disposables);
 			},
diff --git a/src/vs/workbench/api/common/extHost.protocol.ts b/src/vs/workbench/api/common/extHost.protocol.ts
index cb2b3cd4b1f..305568f3b3d 100644
--- a/src/vs/workbench/api/common/extHost.protocol.ts
+++ b/src/vs/workbench/api/common/extHost.protocol.ts
@@ -1613,6 +1613,7 @@ export interface MainThreadWorkspaceShape extends IDisposable {
 	$loadCertificates(): Promise<string[]>;
 	$requestResourceTrust(options: ResourceTrustRequestOptionsDto): Promise<boolean | undefined>;
 	$requestWorkspaceTrust(options?: WorkspaceTrustRequestOptions): Promise<boolean | undefined>;
+	$isResourceTrusted(resource: UriComponents): Promise<boolean>;
 	$registerEditSessionIdentityProvider(handle: number, scheme: string): void;
 	$unregisterEditSessionIdentityProvider(handle: number): void;
 	$registerCanonicalUriProvider(handle: number, scheme: string): void;
@@ -2096,6 +2097,7 @@ export interface ExtHostWorkspaceShape {
 	$acceptWorkspaceData(workspace: IWorkspaceData | null): void;
 	$handleTextSearchResult(result: search.IRawFileMatch2, requestId: number): void;
 	$onDidGrantWorkspaceTrust(): void;
+	$onDidChangeWorkspaceTrustedFolders(): void;
 	$getEditSessionIdentifier(folder: UriComponents, token: CancellationToken): Promise<string | undefined>;
 	$provideEditSessionIdentityMatch(folder: UriComponents, identity1: string, identity2: string, token: CancellationToken): Promise<EditSessionIdentityMatch | undefined>;
 	$onWillCreateEditSessionIdentity(folder: UriComponents, token: CancellationToken, timeout: number): Promise<void>;
diff --git a/src/vs/workbench/api/common/extHostWorkspace.ts b/src/vs/workbench/api/common/extHostWorkspace.ts
index 89b4ecf179a..55ca51e9a64 100644
--- a/src/vs/workbench/api/common/extHostWorkspace.ts
+++ b/src/vs/workbench/api/common/extHostWorkspace.ts
@@ -189,6 +189,9 @@ export class ExtHostWorkspace implements ExtHostWorkspaceShape, IExtHostWorkspac
 	private readonly _onDidGrantWorkspaceTrust = new Emitter<void>();
 	readonly onDidGrantWorkspaceTrust: Event<void> = this._onDidGrantWorkspaceTrust.event;
 
+	private readonly _onDidChangeWorkspaceTrustedFolders = new Emitter<void>();
+	readonly onDidChangeWorkspaceTrustedFolders: Event<void> = this._onDidChangeWorkspaceTrustedFolders.event;
+
 	private readonly _logService: ILogService;
 	private readonly _requestIdProvider: Counter;
 	private readonly _barrier: Barrier;
@@ -821,6 +824,14 @@ export class ExtHostWorkspace implements ExtHostWorkspaceShape, IExtHostWorkspac
 		}
 	}
 
+	$onDidChangeWorkspaceTrustedFolders(): void {
+		this._onDidChangeWorkspaceTrustedFolders.fire();
+	}
+
+	isResourceTrusted(resource: vscode.Uri): Promise<boolean> {
+		return this._proxy.$isResourceTrusted(resource);
+	}
+
 	// --- edit sessions ---
 
 	private _providerHandlePool = 0;
diff --git a/src/vscode-dts/vscode.proposed.workspaceTrust.d.ts b/src/vscode-dts/vscode.proposed.workspaceTrust.d.ts
index 2c8edbd9d18..aad6987c2b5 100644
--- a/src/vscode-dts/vscode.proposed.workspaceTrust.d.ts
+++ b/src/vscode-dts/vscode.proposed.workspaceTrust.d.ts
@@ -34,6 +34,17 @@ declare module 'vscode' {
 	}
 
 	export namespace workspace {
+		/**
+		 * Event fired when the list of workspace trusted folders changes.
+		 */
+		export const onDidChangeWorkspaceTrustedFolders: Event<void>;
+
+		/**
+		 * Check whether the given resource is trusted
+		 * @param resource
+		 */
+		export function isResourceTrusted(resource: Uri): Thenable<boolean>;
+
 		/**
 		 * Prompt the user to chose whether to trust the specified resource (ex: folder)
 		 * @param options Object describing the properties of the resource trust request.