diff --git a/.github/min-versions.json b/.github/min-versions.json
new file mode 100644
index 000000000..ea1de7336
--- /dev/null
+++ b/.github/min-versions.json
@@ -0,0 +1,6 @@
+{
+  "comment": "This file is fetched by the AppMap extension from https://raw.githubusercontent.com/getappmap/vscode-appland/develop/.github/min-versions.json.",
+
+  "vsCode": "1.89.0",
+  "extension": "0.118.2"
+}
diff --git a/src/extension.ts b/src/extension.ts
index 74c00e7ee..fcbb9603b 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -63,6 +63,7 @@ import CommandRegistry from './commands/commandRegistry';
 import AssetService from './assets/assetService';
 import clearNavieAiSettings from './commands/clearNavieAiSettings';
 import EnvironmentVariableService from './services/environmentVariableService';
+import { checkVersions } from './lib/checkVersions';
 
 export async function activate(context: vscode.ExtensionContext): Promise<AppMapService> {
   CommandRegistry.setContext(context).addWaitAlias({
@@ -84,6 +85,8 @@ export async function activate(context: vscode.ExtensionContext): Promise<AppMap
     const extensionState = new ExtensionState(context);
     context.subscriptions.push(extensionState);
 
+    checkVersions(context);
+
     navieConfigurationService(context);
 
     const recommender = new AppMapRecommenderService(extensionState);
diff --git a/src/lib/checkVersions.ts b/src/lib/checkVersions.ts
new file mode 100644
index 000000000..5b9c2b9f0
--- /dev/null
+++ b/src/lib/checkVersions.ts
@@ -0,0 +1,53 @@
+import * as vscode from 'vscode';
+import fetch from 'node-fetch';
+import semverCompare from 'semver/functions/compare';
+import semverValid from 'semver/functions/valid';
+
+const MIN_VERSIONS_JSON_URL =
+  'https://raw.githubusercontent.com/getappmap/vscode-appland/develop/.github/min-versions.json';
+
+async function fetchMinVersions(url: string) {
+  try {
+    const response = await fetch(url);
+    return await response.json();
+  } catch (e) {
+    /* Do nothing if there is no min versions json. */
+  }
+}
+
+export type MinVersions = {
+  vsCode?: string;
+  extension?: string;
+};
+
+export async function checkVersions(
+  context: vscode.ExtensionContext,
+  minVersions?: MinVersions,
+  minVersionsJsonUrl: string = MIN_VERSIONS_JSON_URL
+): Promise<void> {
+  if (minVersions == undefined) minVersions = await fetchMinVersions(minVersionsJsonUrl);
+  if (minVersions == undefined) return;
+
+  const vsCodeIsOld =
+    minVersions.vsCode &&
+    semverValid(minVersions.vsCode, true) &&
+    semverCompare(minVersions.vsCode, vscode.version, true) == 1;
+  const extensionIsOld =
+    minVersions.extension &&
+    semverValid(minVersions.extension, true) &&
+    semverCompare(minVersions.extension, context.extension.packageJSON.version, true) == 1;
+
+  const clauses: string[] = [];
+  if (vsCodeIsOld) clauses.push(`VSCode to v${minVersions.vsCode} or higher`);
+  if (extensionIsOld) clauses.push(`AppMap extension to v${minVersions.extension} or higher`);
+  if (clauses.length > 0) {
+    const choice = await vscode.window.showWarningMessage(
+      `Update Required: Please update ${clauses.join(' and ')}.`,
+      'Update Now'
+    );
+    if (choice == 'Update Now') {
+      if (vsCodeIsOld) vscode.commands.executeCommand('update.checkForUpdate');
+      else vscode.commands.executeCommand('workbench.extensions.action.checkForUpdates');
+    }
+  }
+}
diff --git a/test/integration/lib/checkVersions.test.ts b/test/integration/lib/checkVersions.test.ts
new file mode 100644
index 000000000..2834d1996
--- /dev/null
+++ b/test/integration/lib/checkVersions.test.ts
@@ -0,0 +1,74 @@
+import assert from 'assert';
+import * as vscode from 'vscode';
+import * as semver from 'semver';
+import { SinonSandbox, SinonStub, createSandbox } from 'sinon';
+import MockExtensionContext from '../../mocks/mockExtensionContext';
+import { checkVersions } from '../../../src/lib/checkVersions';
+
+describe('Check VSCode and extension versions', () => {
+  let sinon: SinonSandbox;
+  let context: MockExtensionContext;
+  let showWarningMessageStub: SinonStub;
+  let executeCommandStub: SinonStub;
+
+  beforeEach(() => {
+    sinon = createSandbox();
+    context = new MockExtensionContext();
+
+    showWarningMessageStub = sinon.stub(vscode.window, 'showWarningMessage');
+    showWarningMessageStub.resolves('Update Now' as unknown as vscode.MessageItem);
+    executeCommandStub = sinon.stub(vscode.commands, 'executeCommand');
+  });
+
+  afterEach(() => {
+    context.dispose();
+    sinon.restore();
+  });
+
+  it('warning shown when both versions are old', async () => {
+    // Can't replace vscode.version
+    // sinon.replaceGetter(vscode, 'version', () => '1.82');
+    const minVersions = {
+      vsCode: semver.inc(vscode.version, 'minor') ?? undefined,
+      extension: '0.118.2',
+    };
+    sinon.replace(context.extension.packageJSON, 'version', '0.118.0');
+    await checkVersions(context, minVersions);
+    assert.equal(showWarningMessageStub.callCount, 1);
+    assert.equal(
+      showWarningMessageStub.firstCall.args[0],
+      `Update Required: Please update VSCode to v${minVersions.vsCode} or higher` +
+        ` and AppMap extension to v${minVersions.extension} or higher.`
+    );
+    assert.equal(executeCommandStub.callCount, 1);
+    assert.equal(executeCommandStub.firstCall.args[0], 'update.checkForUpdate');
+  });
+
+  it('warning shown when only extension version is old', async () => {
+    const minVersions = {
+      vsCode: vscode.version,
+      extension: '0.118.2',
+    };
+    sinon.replace(context.extension.packageJSON, 'version', '0.118.0');
+    await checkVersions(context, minVersions);
+    assert.equal(showWarningMessageStub.callCount, 1);
+    assert.equal(
+      showWarningMessageStub.firstCall.args[0],
+      `Update Required: Please update AppMap extension to v${minVersions.extension} or higher.`
+    );
+    assert.equal(executeCommandStub.callCount, 1);
+    assert.equal(
+      executeCommandStub.firstCall.args[0],
+      'workbench.extensions.action.checkForUpdates'
+    );
+  });
+
+  it('no warning when versions are up to date', async () => {
+    await checkVersions(context, {
+      vsCode: vscode.version,
+      extension: context.extension.packageJSON.version,
+    });
+    assert(showWarningMessageStub.notCalled);
+    assert(executeCommandStub.notCalled);
+  });
+});