diff --git a/extensions/typescript-language-features/src/languageFeatures/copilotRelated.ts b/extensions/typescript-language-features/src/languageFeatures/copilotRelated.ts
new file mode 100644
index 0000000000000..f1ceac1a584a7
--- /dev/null
+++ b/extensions/typescript-language-features/src/languageFeatures/copilotRelated.ts
@@ -0,0 +1,86 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as vscode from 'vscode';
+import { isSupportedLanguageMode } from '../configuration/languageIds';
+import { DocumentSelector } from '../configuration/documentSelector';
+import { API } from '../tsServer/api';
+import type * as Proto from '../tsServer/protocol/protocol';
+import { ITypeScriptServiceClient } from '../typescriptService';
+import { conditionalRegistration, requireMinVersion } from './util/dependentRegistration';
+
+const minVersion = API.v570;
+
+export function register(
+	selector: DocumentSelector,
+	client: ITypeScriptServiceClient,
+): vscode.Disposable {
+	return conditionalRegistration([
+		requireMinVersion(client, minVersion),
+	], () => {
+		const ext = vscode.extensions.getExtension('github.copilot');
+		if (!ext) {
+			return new vscode.Disposable(() => { });
+		}
+		const disposers: vscode.Disposable[] = [];
+		ext.activate().then(() => {
+			const relatedAPI = ext.exports as {
+				registerRelatedFilesProvider(
+					providerId: { extensionId: string; languageId: string },
+					callback: (
+						uri: vscode.Uri,
+						context: { flags: Record<string, unknown> },
+						cancellationToken: vscode.CancellationToken
+					) => Promise<{
+						entries: vscode.Uri[];
+						traits?: Array<{ name: string; value: string; includeInPrompt?: boolean; promptTextOverride?: string }>;
+					}>
+				): vscode.Disposable;
+			} | undefined;
+			if (relatedAPI?.registerRelatedFilesProvider) {
+				for (const syntax of selector.syntax) {
+					if (!syntax.language) {
+						continue;
+					}
+					const id = {
+						extensionId: 'vscode.typescript-language-features',
+						languageId: syntax.language
+					};
+					disposers.push(relatedAPI.registerRelatedFilesProvider(id, async (uri, _context, token) => {
+						let document;
+						try {
+							document = await vscode.workspace.openTextDocument(uri);
+						} catch {
+							if (!vscode.window.activeTextEditor) {
+								vscode.window.showErrorMessage(vscode.l10n.t("Related files provider failed. No active text editor."));
+								return { entries: [] };
+							}
+							// something is REALLY wrong if you can't open the active text editor's document, so don't catch that
+							document = await vscode.workspace.openTextDocument(vscode.window.activeTextEditor.document.uri);
+						}
+
+						if (!isSupportedLanguageMode(document)) {
+							vscode.window.showErrorMessage(vscode.l10n.t("Related files provider failed. Copilot requested file with unsupported language mode."));
+							return { entries: [] };
+						}
+
+						const file = client.toOpenTsFilePath(document);
+						if (!file) {
+							return { entries: [] };
+						}
+						// @ts-expect-error until ts5.7
+						const response = await client.execute('copilotRelated', { file, }, token) as Proto.CopilotRelatedResponse;
+						if (response.type !== 'response' || !response.body) {
+							return { entries: [] };
+						}
+						// @ts-expect-error until ts5.7
+						return { entries: response.body.relatedFiles.map(f => client.toResource(f)), traits: [] };
+					}));
+				}
+			}
+		});
+		return vscode.Disposable.from(...disposers);
+	});
+}
diff --git a/extensions/typescript-language-features/src/languageProvider.ts b/extensions/typescript-language-features/src/languageProvider.ts
index 7b95591604bd0..09a4fe3ccc9c6 100644
--- a/extensions/typescript-language-features/src/languageProvider.ts
+++ b/extensions/typescript-language-features/src/languageProvider.ts
@@ -91,6 +91,7 @@ export default class LanguageProvider extends Disposable {
 			import('./languageFeatures/sourceDefinition').then(provider => this._register(provider.register(this.client, this.commandManager))),
 			import('./languageFeatures/tagClosing').then(provider => this._register(provider.register(selector, this.description, this.client))),
 			import('./languageFeatures/typeDefinitions').then(provider => this._register(provider.register(selector, this.client))),
+			import('./languageFeatures/copilotRelated').then(provider => this._register(provider.register(selector, this.client))),
 		]);
 	}
 
diff --git a/extensions/typescript-language-features/src/typescriptService.ts b/extensions/typescript-language-features/src/typescriptService.ts
index 90528ee47dc8c..33d89e1df8d5b 100644
--- a/extensions/typescript-language-features/src/typescriptService.ts
+++ b/extensions/typescript-language-features/src/typescriptService.ts
@@ -77,6 +77,8 @@ interface StandardTsServerRequests {
 	'getMoveToRefactoringFileSuggestions': [Proto.GetMoveToRefactoringFileSuggestionsRequestArgs, Proto.GetMoveToRefactoringFileSuggestions];
 	'linkedEditingRange': [Proto.FileLocationRequestArgs, Proto.LinkedEditingRangeResponse];
 	'mapCode': [Proto.MapCodeRequestArgs, Proto.MapCodeResponse];
+	// @ts-expect-error until ts5.7
+	'copilotRelated': [Proto.FileRequestArgs, Proto.CopilotRelatedResponse];
 	'getPasteEdits': [Proto.GetPasteEditsRequestArgs, Proto.GetPasteEditsResponse];
 	'preparePasteEdits': [Proto.PreparePasteEditsRequestArgs, Proto.PreparePasteEditsResponse];
 }