diff --git a/ember-resources/src/util/modal-manager.ts b/ember-resources/src/util/modal-manager.ts
new file mode 100644
index 000000000..ee6f99fc0
--- /dev/null
+++ b/ember-resources/src/util/modal-manager.ts
@@ -0,0 +1,108 @@
+import { tracked } from '@glimmer/tracking';
+
+interface ValuedResult<TValue> {
+  reason: 'confirmed' | 'rejected';
+  value: TValue;
+}
+
+interface CancelledResult {
+  reason: 'cancelled';
+}
+
+type Result<TValue> = ValuedResult<TValue> | CancelledResult;
+
+interface Controller {
+  open: () => void;
+  close: () => void;
+}
+
+const noop = () => {
+  return;
+};
+
+/**
+ * A utility to manage modal dialog boxes. It provides an isOpen tracked
+ * property that can be used in templates to show/hide a modal dialog.
+ *
+ * This utility helps the code logic by offering a promise that will result in
+ * the conclusion of the modal dialog. It also allows you to provide the dialog
+ * component a simple manager interface that it can use to confirm, cancel, and
+ * even reject based on user input. That result can then be used for control
+ * flow by that initiator or even passed around as a promise as needed.
+ *
+ * @example
+ * ```ts
+ * import Component from '@glimmer/component';
+ * import { ModalManager } from 'ember-resources/utils/modal-manager';
+ *
+ * class Demo extends Component {
+ *   manager = new ModalManager();
+ *   openAndManageModal = async () => {
+ *     let { reason, value } = await this.manager.open();
+ *     if (reason !== 'confirmed') return;
+ *     doSomethingWith(value);
+ *   }
+ * }
+ * ```
+ *
+ * ```hbs
+ * <button type="button" {{on "click" this.openAndManageModal}}></button>
+ * {{#if this.manager.isOpen}}
+ *   <MyModal @manager={{this.manager}} />
+ * {{/if}}
+ * ```
+ */
+export class ModalManager<TValue = undefined> {
+  #openModal: () => void = noop;
+  #closeModal: () => void = noop;
+  #resolve: (result: Result<TValue>) => void = noop;
+  #reject: (error: Error) => void = noop;
+
+  @tracked _isOpen = false;
+
+  get isOpen() {
+    return this._isOpen;
+  }
+
+  open = () => {
+    return new Promise<Result<TValue>>((resolve, reject) => {
+      this._isOpen = true;
+      this.#resolve = resolve;
+      this.#reject = reject;
+      this.#openModal();
+    }).finally(() => {
+      this.#closeModal();
+      this._isOpen = true;
+    });
+  };
+
+  cancel = () => {
+    this.#resolve({ reason: 'cancelled' });
+  };
+
+  confirm = (value: TValue) => {
+    this.#resolve({ reason: 'confirmed', value });
+  };
+
+  reject = (value: TValue) => {
+    this.#resolve({ reason: 'rejected', value });
+  };
+
+  error = (error: Error) => {
+    this.#reject(error);
+  };
+
+  delegateTo(controller: Controller) {
+    this.#openModal = () => controller.open();
+    this.#closeModal = () => controller.close();
+  }
+
+  static withDelegate(factory: (manager: ModalManager) => Controller) {
+    let manager = new ModalManager();
+    let controller = factory(manager);
+
+    manager.delegateTo(controller);
+
+    return manager;
+  }
+}
diff --git a/testing/ember-app/tests/utils/modal-manager/js-test.ts b/testing/ember-app/tests/utils/modal-manager/js-test.ts
new file mode 100644
index 000000000..6377897ea
--- /dev/null
+++ b/testing/ember-app/tests/utils/modal-manager/js-test.ts
@@ -0,0 +1,90 @@
+import { module, test } from 'qunit';
+import { setupTest } from 'ember-qunit';
+
+import { ModalManager } from 'ember-resources/util/modal-manager';
+
+module('Utils | modal-manager | js', function (hooks) {
+  setupTest(hooks);
+
+  test('manages isOpen flag', async function(assert) {
+    let subject = new ModalManager();
+    assert.false(subject.isOpen, 'isOpen false');
+    let resultPromise = subject.open();
+    assert.true(subject.isOpen, 'isOpen troue');
+    subject.cancel();
+    await resultPromise;
+    assert.false(subject.isOpen, 'isOpen false');
+  });
+
+  test('can be cancelled', async function(assert) {
+    let subject = new ModalManager();
+    let resultPromise = subject.open();
+    subject.cancel();
+    let { reason } = await resultPromise;
+    assert.equal(reason, 'cancelled');
+  });
+
+  test('can be confirmed', async function(assert) {
+    let subject = new ModalManager();
+    let resultPromise = subject.open();
+    subject.confirm('test-value');
+    let { reason, value } = await resultPromise;
+    assert.equal(reason, 'confirmed');
+    assert.equal(value, 'test-value');
+  });
+
+  test('can be rejected', async function(assert) {
+    let subject = new ModalManager();
+    let resultPromise = subject.open();
+    subject.reject('test-value');
+    let { reason, value } = await resultPromise;
+    assert.equal(reason, 'rejected');
+    assert.equal(value, 'test-value');
+  });
+
+  test('can be errored', async function(assert) {
+    let subject = new ModalManager();
+    let resultPromise = subject.open();
+    subject.error(new Error('test-error'));
+    await assert.rejects(resultPromise, /test-error/);
+  });
+
+  test('can delegate opening and closing', async function(assert) {
+    class TestController {
+      open() {
+        assert.step('opened');
+      }
+      close() {
+        assert.step('closed');
+      }
+    }
+    let testController = new TestController();
+    let subject = new ModalManager();
+    subject.delegateTo(testController);
+    let resultPromise = subject.open();
+    subject.cancel();
+    await resultPromise;
+    assert.verifySteps(['opened', 'closed']);
+  });
+
+  test('provides a factory method for inline delegation', async function(assert) {
+    class TestController {
+      open() {
+        assert.step('opened');
+      }
+      close() {
+        assert.step('closed');
+      }
+    }
+    let calledWith: ModalManager;
+    let subject = ModalManager.withDelegate((manager: ModalManager) => {
+      calledWith = manager;
+      return new TestController();
+    });
+    let resultPromise = subject.open();
+    subject.cancel();
+    await resultPromise;
+    assert.verifySteps(['opened', 'closed']);
+    assert.strictEqual(calledWith, subject);
+  });
+});
diff --git a/testing/ember-app/tests/utils/modal-manager/rendering-test.ts b/testing/ember-app/tests/utils/modal-manager/rendering-test.ts
new file mode 100644
index 000000000..5a9723cc2
--- /dev/null
+++ b/testing/ember-app/tests/utils/modal-manager/rendering-test.ts
@@ -0,0 +1,53 @@
+import Component from '@glimmer/component';
+import { setComponentTemplate } from '@ember/component';
+import { click, render } from '@ember/test-helpers';
+import { hbs } from 'ember-cli-htmlbars';
+import { module, test } from 'qunit';
+import { setupRenderingTest } from 'ember-qunit';
+
+import { ModalManager } from 'ember-resources/util/modal-manager';
+
+module('Utils | modal-manager | rendering', function (hooks) {
+  setupRenderingTest(hooks);
+
+  test('it works', async function (assert) {
+    class Test extends Component {
+      manager = new ModalManager();
+      openModal = async () => {
+        assert.step('modal opened');
+        let { result, value = '' } = await this.manager.open();
+        assert.step(`modal ${result} (${value})`);
+      };
+    }
+
+    setComponentTemplate<typeof Test>(
+      hbs`
+        <button id="open" type="button" {{on "click" this.openModal}}></button>
+        {{#if this.manager.isOpen}}
+          <button id="cancel" type="button" {{on "click" this.manager.cancel}}></button>
+          <button id="confirm" type="button" {{on "click" (fn this.manager.confirm "test-confirm")}}></button>
+          <button id="reject" type="button" {{on "click" (fn this.manager.reject "test-reject")}}></button>
+        {{/each}}
+      `,
+      Test
+    );
+
+    this.setProperties({ Test });
+    await render(hbs`<this.Test />`);
+    await click('#open');
+    await click('#cancel');
+    await click('#open');
+    await click('#confirm');
+    await click('#open');
+    await click('#reject');
+
+    assert.verifySteps([
+      'modal opened',
+      'modal cancelled ()',
+      'modal opened',
+      'modal confirmed (test-confirm)',
+      'modal opened',
+      'modal rejected (test-reject)',
+    ]);
+  });
+});