diff --git a/src/vs/workbench/contrib/testing/common/testProfileService.ts b/src/vs/workbench/contrib/testing/common/testProfileService.ts
index ecdb9ffcd63..60d5972e130 100644
--- a/src/vs/workbench/contrib/testing/common/testProfileService.ts
+++ b/src/vs/workbench/contrib/testing/common/testProfileService.ts
@@ -241,11 +241,31 @@ export class TestProfileService implements ITestProfileService {
 
 	/** @inheritdoc */
 	public setGroupDefaultProfiles(group: TestRunProfileBitset, profiles: ITestRunProfile[]) {
-		this.preferredDefaults.store({
+		const next = {
 			...this.preferredDefaults.get(),
 			[group]: profiles.map(c => ({ profileId: c.profileId, controllerId: c.controllerId })),
-		});
+		};
 
+		// When switching a run/debug profile, if the controller has a same-named
+		// profile in the other group, use that instead of anything else that was selected.
+		if (group === TestRunProfileBitset.Run || group === TestRunProfileBitset.Debug) {
+			const otherGroup = group === TestRunProfileBitset.Run ? TestRunProfileBitset.Debug : TestRunProfileBitset.Run;
+
+			const previousDefaults = next[otherGroup] || [];
+			let newDefaults = previousDefaults.slice();
+			for (const [ctrlId, { profiles: ctrlProfiles }] of this.controllerProfiles) {
+				const labels = new Set(profiles.filter(p => p.controllerId === ctrlId).map(p => p.label));
+				const nextByLabels = ctrlProfiles.filter(p => labels.has(p.label) && p.group === otherGroup);
+				if (nextByLabels.length) {
+					newDefaults = newDefaults.filter(p => p.controllerId !== ctrlId);
+					newDefaults.push(...nextByLabels.map(p => ({ profileId: p.profileId, controllerId: p.controllerId })));
+				}
+			}
+
+			next[otherGroup] = newDefaults;
+		}
+
+		this.preferredDefaults.store(next);
 		this.changeEmitter.fire();
 	}
 
diff --git a/src/vs/workbench/contrib/testing/test/common/testProfileService.test.ts b/src/vs/workbench/contrib/testing/test/common/testProfileService.test.ts
new file mode 100644
index 00000000000..f12f301beae
--- /dev/null
+++ b/src/vs/workbench/contrib/testing/test/common/testProfileService.test.ts
@@ -0,0 +1,117 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+
+
+import * as assert from 'assert';
+import { MockContextKeyService } from 'vs/platform/keybinding/test/common/mockKeybindingService';
+import { TestProfileService } from 'vs/workbench/contrib/testing/common/testProfileService';
+import { ITestRunProfile, TestRunProfileBitset } from 'vs/workbench/contrib/testing/common/testTypes';
+import { TestStorageService } from 'vs/workbench/test/common/workbenchTestServices';
+
+suite('Workbench - TestProfileService', () => {
+	let t: TestProfileService;
+	let idCounter = 0;
+	setup(() => {
+		idCounter = 0;
+		t = new TestProfileService(
+			new MockContextKeyService(),
+			new TestStorageService(),
+		);
+	});
+
+	const addProfile = (profile: Partial<ITestRunProfile>) => {
+		const p: ITestRunProfile = {
+			controllerId: 'ctrlId',
+			group: TestRunProfileBitset.Run,
+			isDefault: true,
+			label: 'profile',
+			profileId: idCounter++,
+			hasConfigurationHandler: false,
+			tag: null,
+			...profile,
+		};
+
+		t.addProfile(null as any, p);
+		return p;
+	};
+
+	const expectProfiles = (expected: ITestRunProfile[], actual: string[]) => {
+		const e = expected.map(e => e.label).sort();
+		const a = actual.sort();
+		assert.deepStrictEqual(e, a);
+	};
+
+	test('getGroupDefaultProfiles', () => {
+		addProfile({ isDefault: true, group: TestRunProfileBitset.Debug, label: 'a' });
+		addProfile({ isDefault: false, group: TestRunProfileBitset.Debug, label: 'b' });
+		addProfile({ isDefault: true, group: TestRunProfileBitset.Run, label: 'c' });
+		addProfile({ isDefault: true, group: TestRunProfileBitset.Run, label: 'd', controllerId: '2' });
+		addProfile({ isDefault: false, group: TestRunProfileBitset.Run, label: 'e', controllerId: '2' });
+		expectProfiles(t.getGroupDefaultProfiles(TestRunProfileBitset.Run), ['c', 'd']);
+		expectProfiles(t.getGroupDefaultProfiles(TestRunProfileBitset.Debug), ['a']);
+	});
+
+	suite('setGroupDefaultProfiles', () => {
+		test('applies simple changes', () => {
+			const p1 = addProfile({ isDefault: false, group: TestRunProfileBitset.Debug, label: 'a' });
+			addProfile({ isDefault: false, group: TestRunProfileBitset.Debug, label: 'b' });
+			const p3 = addProfile({ isDefault: false, group: TestRunProfileBitset.Run, label: 'c' });
+			addProfile({ isDefault: false, group: TestRunProfileBitset.Run, label: 'd' });
+
+			t.setGroupDefaultProfiles(TestRunProfileBitset.Run, [p3]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Run), [p3]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Debug), [p1]);
+		});
+
+		test('syncs labels if same', () => {
+			const p1 = addProfile({ isDefault: false, group: TestRunProfileBitset.Debug, label: 'a' });
+			const p2 = addProfile({ isDefault: false, group: TestRunProfileBitset.Debug, label: 'b' });
+			const p3 = addProfile({ isDefault: false, group: TestRunProfileBitset.Run, label: 'a' });
+			const p4 = addProfile({ isDefault: false, group: TestRunProfileBitset.Run, label: 'b' });
+
+			t.setGroupDefaultProfiles(TestRunProfileBitset.Run, [p3]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Run), [p3]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Debug), [p1]);
+
+			t.setGroupDefaultProfiles(TestRunProfileBitset.Debug, [p2]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Run), [p4]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Debug), [p2]);
+		});
+
+		test('does not mess up sync for multiple controllers', () => {
+			// ctrl a and b both of have their own labels. ctrl c does not and should be unaffected
+			const p1 = addProfile({ isDefault: false, controllerId: 'a', group: TestRunProfileBitset.Debug, label: 'a' });
+			const p2 = addProfile({ isDefault: false, controllerId: 'b', group: TestRunProfileBitset.Debug, label: 'b1' });
+			const p3 = addProfile({ isDefault: false, controllerId: 'b', group: TestRunProfileBitset.Debug, label: 'b2' });
+			const p4 = addProfile({ isDefault: false, controllerId: 'c', group: TestRunProfileBitset.Debug, label: 'c1' });
+
+			const p5 = addProfile({ isDefault: false, controllerId: 'a', group: TestRunProfileBitset.Run, label: 'a' });
+			const p6 = addProfile({ isDefault: false, controllerId: 'b', group: TestRunProfileBitset.Run, label: 'b1' });
+			const p7 = addProfile({ isDefault: false, controllerId: 'b', group: TestRunProfileBitset.Run, label: 'b2' });
+			const p8 = addProfile({ isDefault: false, controllerId: 'b', group: TestRunProfileBitset.Run, label: 'b3' });
+
+			// same profile on both
+			t.setGroupDefaultProfiles(TestRunProfileBitset.Debug, [p3]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Run), [p7]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Debug), [p3]);
+
+			// different profile, other should be unaffected
+			t.setGroupDefaultProfiles(TestRunProfileBitset.Run, [p8]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Run), [p8]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Debug), [p3]);
+
+			// multiple changes in one go, with unmatched c
+			t.setGroupDefaultProfiles(TestRunProfileBitset.Debug, [p1, p2, p4]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Run), [p5, p6]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Debug), [p1, p2, p4]);
+
+			// identity
+			t.setGroupDefaultProfiles(TestRunProfileBitset.Run, [p5, p8]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Run), [p5, p8]);
+			assert.deepStrictEqual(t.getGroupDefaultProfiles(TestRunProfileBitset.Debug), [p2, p4, p1]);
+		});
+	});
+});