diff --git a/src/components-examples/material/dialog/dialog-harness/dialog-harness-example.spec.ts b/src/components-examples/material/dialog/dialog-harness/dialog-harness-example.spec.ts
index 00b02c34cbaf..3904bdeaf671 100644
--- a/src/components-examples/material/dialog/dialog-harness/dialog-harness-example.spec.ts
+++ b/src/components-examples/material/dialog/dialog-harness/dialog-harness-example.spec.ts
@@ -12,6 +12,7 @@ import {NoopAnimationsModule} from '@angular/platform-browser/animations';
 
 describe('DialogHarnessExample', () => {
   let fixture: ComponentFixture<DialogHarnessExample>;
+  let fixtureTwo: ComponentFixture<DialogHarnessExample>;
   let loader: HarnessLoader;
 
   beforeAll(() => {
@@ -27,6 +28,8 @@ describe('DialogHarnessExample', () => {
     }).compileComponents();
     fixture = TestBed.createComponent(DialogHarnessExample);
     fixture.detectChanges();
+    fixtureTwo = TestBed.createComponent(DialogHarnessExample);
+    fixtureTwo.detectChanges();
     loader = TestbedHarnessEnvironment.documentRootLoader(fixture);
   }));
 
@@ -38,7 +41,7 @@ describe('DialogHarnessExample', () => {
 
   it('should load harness for dialog with specific id', async () => {
     fixture.componentInstance.open({id: 'my-dialog'});
-    fixture.componentInstance.open({id: 'other'});
+    fixtureTwo.componentInstance.open({id: 'other'});
     let dialogs = await loader.getAllHarnesses(MatDialogHarness);
     expect(dialogs.length).toBe(2);
 
@@ -48,7 +51,7 @@ describe('DialogHarnessExample', () => {
 
   it('should be able to get role of dialog', async () => {
     fixture.componentInstance.open({role: 'alertdialog'});
-    fixture.componentInstance.open({role: 'dialog'});
+    fixtureTwo.componentInstance.open({role: 'dialog'});
     const dialogs = await loader.getAllHarnesses(MatDialogHarness);
     expect(await dialogs[0].getRole()).toBe('alertdialog');
     expect(await dialogs[1].getRole()).toBe('dialog');
@@ -57,7 +60,7 @@ describe('DialogHarnessExample', () => {
 
   it('should be able to close dialog', async () => {
     fixture.componentInstance.open({disableClose: true});
-    fixture.componentInstance.open();
+    fixtureTwo.componentInstance.open();
     let dialogs = await loader.getAllHarnesses(MatDialogHarness);
 
     expect(dialogs.length).toBe(2);
diff --git a/src/material-experimental/mdc-dialog/dialog.spec.ts b/src/material-experimental/mdc-dialog/dialog.spec.ts
index 089153936790..e06bd0d57d09 100644
--- a/src/material-experimental/mdc-dialog/dialog.spec.ts
+++ b/src/material-experimental/mdc-dialog/dialog.spec.ts
@@ -615,8 +615,8 @@ describe('MDC-based MatDialog', () => {
 
   it('should close all of the dialogs', fakeAsync(() => {
        dialog.open(PizzaMsg);
-       dialog.open(PizzaMsg);
-       dialog.open(PizzaMsg);
+       dialog.open(PizzaMsgTwo);
+       dialog.open(PizzaMsgThree);
 
        expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(3);
 
@@ -629,7 +629,7 @@ describe('MDC-based MatDialog', () => {
 
   it('should close all dialogs when the user goes forwards/backwards in history', fakeAsync(() => {
        dialog.open(PizzaMsg);
-       dialog.open(PizzaMsg);
+       dialog.open(PizzaMsgTwo);
 
        expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(2);
 
@@ -642,7 +642,7 @@ describe('MDC-based MatDialog', () => {
 
   it('should close all open dialogs when the location hash changes', fakeAsync(() => {
        dialog.open(PizzaMsg);
-       dialog.open(PizzaMsg);
+       dialog.open(PizzaMsgTwo);
 
        expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(2);
 
@@ -655,8 +655,8 @@ describe('MDC-based MatDialog', () => {
 
   it('should close all of the dialogs when the injectable is destroyed', fakeAsync(() => {
        dialog.open(PizzaMsg);
-       dialog.open(PizzaMsg);
-       dialog.open(PizzaMsg);
+       dialog.open(PizzaMsgTwo);
+       dialog.open(PizzaMsgThree);
 
        expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(3);
 
@@ -685,7 +685,7 @@ describe('MDC-based MatDialog', () => {
 
   it('should allow the consumer to disable closing a dialog on navigation', fakeAsync(() => {
        dialog.open(PizzaMsg);
-       dialog.open(PizzaMsg, {closeOnNavigation: false});
+       dialog.open(PizzaMsgTwo, {closeOnNavigation: false});
 
        expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(2);
 
@@ -774,7 +774,7 @@ describe('MDC-based MatDialog', () => {
 
   it('should assign a unique id to each dialog', () => {
     const one = dialog.open(PizzaMsg);
-    const two = dialog.open(PizzaMsg);
+    const two = dialog.open(PizzaMsgTwo);
 
     expect(one.id).toBeTruthy();
     expect(two.id).toBeTruthy();
@@ -1188,7 +1188,7 @@ describe('MDC-based MatDialog', () => {
          expect(document.activeElement!.id)
              .not.toBe(
                  'dialog-trigger',
-                 'Expcted the focus not to have changed before the animation finishes.');
+                 'Expected the focus not to have changed before the animation finishes.');
 
          flushMicrotasks();
          viewContainerFixture.detectChanges();
@@ -1247,7 +1247,8 @@ describe('MDC-based MatDialog', () => {
 
          tick(500);
          viewContainerFixture.detectChanges();
-         expect(lastFocusOrigin!).toBeNull('Expected the trigger button to be blurred');
+         expect(lastFocusOrigin!)
+             .withContext('Expected the trigger button to be blurred').toBeNull();
 
          dispatchKeyboardEvent(document.body, 'keydown', ESCAPE);
 
@@ -1256,7 +1257,8 @@ describe('MDC-based MatDialog', () => {
          tick(500);
 
          expect(lastFocusOrigin!)
-             .toBe('keyboard', 'Expected the trigger button to be focused via keyboard');
+             .withContext('Expected the trigger button to be focused via keyboard')
+             .toBe('keyboard');
 
          focusMonitor.stopMonitoring(button);
          document.body.removeChild(button);
@@ -1281,7 +1283,8 @@ describe('MDC-based MatDialog', () => {
 
          tick(500);
          viewContainerFixture.detectChanges();
-         expect(lastFocusOrigin!).toBeNull('Expected the trigger button to be blurred');
+         expect(lastFocusOrigin!)
+             .withContext('Expected the trigger button to be blurred').toBeNull();
 
          const backdrop =
              overlayContainerElement.querySelector('.cdk-overlay-backdrop') as HTMLElement;
@@ -1291,7 +1294,8 @@ describe('MDC-based MatDialog', () => {
          tick(500);
 
          expect(lastFocusOrigin!)
-             .toBe('mouse', 'Expected the trigger button to be focused via mouse');
+             .withContext('Expected the trigger button to be focused via mouse')
+             .toBe('mouse');
 
          focusMonitor.stopMonitoring(button);
          document.body.removeChild(button);
@@ -1317,7 +1321,8 @@ describe('MDC-based MatDialog', () => {
 
          tick(500);
          viewContainerFixture.detectChanges();
-         expect(lastFocusOrigin!).toBeNull('Expected the trigger button to be blurred');
+         expect(lastFocusOrigin!)
+             .withContext('Expected the trigger button to be blurred').toBeNull();
 
          const closeButton =
              overlayContainerElement.querySelector('button[mat-dialog-close]') as HTMLElement;
@@ -1330,7 +1335,8 @@ describe('MDC-based MatDialog', () => {
          tick(500);
 
          expect(lastFocusOrigin!)
-             .toBe('keyboard', 'Expected the trigger button to be focused via keyboard');
+             .withContext('Expected the trigger button to be focused via keyboard')
+             .toBe('keyboard');
 
          focusMonitor.stopMonitoring(button);
          document.body.removeChild(button);
@@ -1355,7 +1361,8 @@ describe('MDC-based MatDialog', () => {
 
          tick(500);
          viewContainerFixture.detectChanges();
-         expect(lastFocusOrigin!).toBeNull('Expected the trigger button to be blurred');
+         expect(lastFocusOrigin!)
+             .withContext('Expected the trigger button to be blurred').toBeNull();
 
          const closeButton =
              overlayContainerElement.querySelector('button[mat-dialog-close]') as HTMLElement;
@@ -1369,7 +1376,8 @@ describe('MDC-based MatDialog', () => {
          tick(500);
 
          expect(lastFocusOrigin!)
-             .toBe('mouse', 'Expected the trigger button to be focused via mouse');
+             .withContext('Expected the trigger button to be focused via mouse')
+             .toBe('mouse');
 
          focusMonitor.stopMonitoring(button);
          document.body.removeChild(button);
@@ -1959,12 +1967,26 @@ class ComponentWithTemplateRef {
   }
 }
 
-/** Simple component for testing ComponentPortal. */
+/** Simple components for testing ComponentPortal and multiple dialogs. */
 @Component({template: '<p>Pizza</p> <input> <button>Close</button>'})
 class PizzaMsg {
-  constructor(
-      public dialogRef: MatDialogRef<PizzaMsg>, public dialogInjector: Injector,
-      public directionality: Directionality) {}
+  constructor(public dialogRef: MatDialogRef<PizzaMsg>,
+              public dialogInjector: Injector,
+              public directionality: Directionality) {}
+}
+
+@Component({template: '<p>Pizza</p> <input> <button>Close</button>'})
+class PizzaMsgTwo {
+  constructor(public dialogRef: MatDialogRef<PizzaMsgTwo>,
+              public dialogInjector: Injector,
+              public directionality: Directionality) {}
+}
+
+@Component({template: '<p>Pizza</p> <input> <button>Close</button>'})
+class PizzaMsgThree {
+  constructor(public dialogRef: MatDialogRef<PizzaMsgThree>,
+              public dialogInjector: Injector,
+              public directionality: Directionality) {}
 }
 
 @Component({
@@ -2035,6 +2057,8 @@ const TEST_DIRECTIVES = [
   ComponentWithChildViewContainer,
   ComponentWithTemplateRef,
   PizzaMsg,
+  PizzaMsgTwo,
+  PizzaMsgThree,
   DirectiveWithViewContainer,
   ComponentWithOnPushViewContainer,
   ContentElementDialog,
@@ -2052,6 +2076,8 @@ const TEST_DIRECTIVES = [
     ComponentWithChildViewContainer,
     ComponentWithTemplateRef,
     PizzaMsg,
+    PizzaMsgTwo,
+    PizzaMsgThree,
     ContentElementDialog,
     DialogWithInjectedData,
     DialogWithoutFocusableElements,
diff --git a/src/material/dialog/dialog-animations.ts b/src/material/dialog/dialog-animations.ts
index dbb8f4358f57..da676784890a 100644
--- a/src/material/dialog/dialog-animations.ts
+++ b/src/material/dialog/dialog-animations.ts
@@ -14,6 +14,12 @@ import {
   AnimationTriggerMetadata,
 } from '@angular/animations';
 
+/**
+ * Animation transition time used by MatDialog.
+ * @docs-private
+ */
+export const _transitionTime = 150;
+
 /**
  * Animations used by MatDialog.
  * @docs-private
@@ -28,7 +34,7 @@ export const matDialogAnimations: {
     // decimate the animation performance. Leaving it as `none` solves both issues.
     state('void, exit', style({opacity: 0, transform: 'scale(0.7)'})),
     state('enter', style({transform: 'none'})),
-    transition('* => enter', animate('150ms cubic-bezier(0, 0, 0.2, 1)',
+    transition('* => enter', animate(`${_transitionTime}ms cubic-bezier(0, 0, 0.2, 1)`,
         style({transform: 'none', opacity: 1}))),
     transition('* => void, * => exit',
         animate('75ms cubic-bezier(0.4, 0.0, 0.2, 1)', style({opacity: 0}))),
diff --git a/src/material/dialog/dialog-container.ts b/src/material/dialog/dialog-container.ts
index e66bae7eec05..4c1946ac2971 100644
--- a/src/material/dialog/dialog-container.ts
+++ b/src/material/dialog/dialog-container.ts
@@ -114,9 +114,6 @@ export abstract class _MatDialogContainerBase extends BasePortalOutlet {
     // Save the previously focused element. This element will be re-focused
     // when the dialog closes.
     this._capturePreviouslyFocusedElement();
-    // Move focus onto the dialog immediately in order to prevent the user
-    // from accidentally opening multiple dialogs at the same time.
-    this._focusDialogContainer();
   }
 
   /**
@@ -218,7 +215,13 @@ export abstract class _MatDialogContainerBase extends BasePortalOutlet {
         break;
       case true:
       case 'first-tabbable':
-        this._focusTrap.focusInitialElementWhenReady();
+        this._focusTrap.focusInitialElementWhenReady().then(focusedSuccessfully => {
+          // If we weren't able to find a focusable element in the dialog, then focus the dialog
+          // container instead.
+          if (!focusedSuccessfully) {
+            this._focusDialogContainer();
+          }
+        });
         break;
       case 'first-heading':
         this._focusByCssSelector('h1, h2, h3, h4, h5, h6, [role="heading"]');
diff --git a/src/material/dialog/dialog.spec.ts b/src/material/dialog/dialog.spec.ts
index 9bc880dd75ca..7ba3f9f96ca6 100644
--- a/src/material/dialog/dialog.spec.ts
+++ b/src/material/dialog/dialog.spec.ts
@@ -670,8 +670,8 @@ describe('MatDialog', () => {
 
   it('should close all of the dialogs', fakeAsync(() => {
     dialog.open(PizzaMsg);
-    dialog.open(PizzaMsg);
-    dialog.open(PizzaMsg);
+    dialog.open(PizzaMsgTwo);
+    dialog.open(PizzaMsgThree);
 
     expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(3);
 
@@ -697,7 +697,7 @@ describe('MatDialog', () => {
 
   it('should close all dialogs when the user goes forwards/backwards in history', fakeAsync(() => {
     dialog.open(PizzaMsg);
-    dialog.open(PizzaMsg);
+    dialog.open(PizzaMsgTwo);
 
     expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(2);
 
@@ -710,7 +710,7 @@ describe('MatDialog', () => {
 
   it('should close all open dialogs when the location hash changes', fakeAsync(() => {
     dialog.open(PizzaMsg);
-    dialog.open(PizzaMsg);
+    dialog.open(PizzaMsgTwo);
 
     expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(2);
 
@@ -723,8 +723,8 @@ describe('MatDialog', () => {
 
   it('should close all of the dialogs when the injectable is destroyed', fakeAsync(() => {
     dialog.open(PizzaMsg);
-    dialog.open(PizzaMsg);
-    dialog.open(PizzaMsg);
+    dialog.open(PizzaMsgTwo);
+    dialog.open(PizzaMsgThree);
 
     expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(3);
 
@@ -754,7 +754,7 @@ describe('MatDialog', () => {
 
   it('should allow the consumer to disable closing a dialog on navigation', fakeAsync(() => {
     dialog.open(PizzaMsg);
-    dialog.open(PizzaMsg, {closeOnNavigation: false});
+    dialog.open(PizzaMsgTwo, {closeOnNavigation: false});
 
     expect(overlayContainerElement.querySelectorAll('mat-dialog-container').length).toBe(2);
 
@@ -849,7 +849,7 @@ describe('MatDialog', () => {
 
   it('should assign a unique id to each dialog', () => {
     const one = dialog.open(PizzaMsg);
-    const two = dialog.open(PizzaMsg);
+    const two = dialog.open(PizzaMsgTwo);
 
     expect(one.id).toBeTruthy();
     expect(two.id).toBeTruthy();
@@ -1320,7 +1320,7 @@ describe('MatDialog', () => {
 
       tick(500);
       viewContainerFixture.detectChanges();
-      expect(lastFocusOrigin!).toBeNull('Expected the trigger button to be blurred');
+      expect(lastFocusOrigin!).toBe('program');
 
       dispatchKeyboardEvent(document.body, 'keydown', ESCAPE);
 
@@ -1329,7 +1329,8 @@ describe('MatDialog', () => {
       tick(500);
 
       expect(lastFocusOrigin!)
-        .toBe('keyboard', 'Expected the trigger button to be focused via keyboard');
+        .withContext('Expected the trigger button to be focused via keyboard')
+        .toBe('keyboard');
 
       focusMonitor.stopMonitoring(button);
       document.body.removeChild(button);
@@ -1353,7 +1354,7 @@ describe('MatDialog', () => {
 
       tick(500);
       viewContainerFixture.detectChanges();
-      expect(lastFocusOrigin!).toBeNull('Expected the trigger button to be blurred');
+      expect(lastFocusOrigin!).toBe('program');
 
       const backdrop = overlayContainerElement
           .querySelector('.cdk-overlay-backdrop') as HTMLElement;
@@ -1363,7 +1364,8 @@ describe('MatDialog', () => {
       tick(500);
 
       expect(lastFocusOrigin!)
-        .toBe('mouse', 'Expected the trigger button to be focused via mouse');
+        .withContext('Expected the trigger button to be focused via mouse')
+        .toBe('mouse');
 
       focusMonitor.stopMonitoring(button);
       document.body.removeChild(button);
@@ -1384,12 +1386,18 @@ describe('MatDialog', () => {
       // Patch the element focus after the initial and real focus, because otherwise the
       // `activeElement` won't be set, and the dialog won't be able to restore focus to an element.
       patchElementFocus(button);
+      expect(lastFocusOrigin!)
+        .withContext('Expected the trigger button to be focused via program')
+        .toBe('program');
 
       dialog.open(ContentElementDialog, {viewContainerRef: testViewContainerRef});
 
       tick(500);
       viewContainerFixture.detectChanges();
-      expect(lastFocusOrigin!).toBeNull('Expected the trigger button to be blurred');
+      tick(500);
+      expect(lastFocusOrigin!)
+        .withContext('Expected the trigger button to be blurred')
+        .toBeNull();
 
       const closeButton = overlayContainerElement
         .querySelector('button[mat-dialog-close]') as HTMLElement;
@@ -1402,7 +1410,8 @@ describe('MatDialog', () => {
       tick(500);
 
       expect(lastFocusOrigin!)
-        .toBe('keyboard', 'Expected the trigger button to be focused via keyboard');
+        .withContext('Expected the trigger button to be focused via keyboard')
+        .toBe('keyboard');
 
       focusMonitor.stopMonitoring(button);
       document.body.removeChild(button);
@@ -1421,12 +1430,18 @@ describe('MatDialog', () => {
       // Patch the element focus after the initial and real focus, because otherwise the
       // `activeElement` won't be set, and the dialog won't be able to restore focus to an element.
       patchElementFocus(button);
+      expect(lastFocusOrigin!)
+        .withContext('Expected the trigger button to be focused via program')
+        .toBe('program');
 
       dialog.open(ContentElementDialog, {viewContainerRef: testViewContainerRef});
 
       tick(500);
       viewContainerFixture.detectChanges();
-      expect(lastFocusOrigin!).toBeNull('Expected the trigger button to be blurred');
+      tick(500);
+      expect(lastFocusOrigin!)
+        .withContext('Expected the trigger button to be blurred')
+        .toBeNull();
 
       const closeButton = overlayContainerElement
         .querySelector('button[mat-dialog-close]') as HTMLElement;
@@ -1440,7 +1455,8 @@ describe('MatDialog', () => {
       tick(500);
 
       expect(lastFocusOrigin!)
-        .toBe('mouse', 'Expected the trigger button to be focused via mouse');
+        .withContext('Expected the trigger button to be focused via mouse')
+        .toBe('mouse');
 
       focusMonitor.stopMonitoring(button);
       document.body.removeChild(button);
@@ -2020,7 +2036,7 @@ class ComponentWithTemplateRef {
   }
 }
 
-/** Simple component for testing ComponentPortal. */
+/** Simple components for testing ComponentPortal and multiple dialogs. */
 @Component({template: '<p>Pizza</p> <input> <button>Close</button>'})
 class PizzaMsg {
   constructor(public dialogRef: MatDialogRef<PizzaMsg>,
@@ -2028,6 +2044,20 @@ class PizzaMsg {
               public directionality: Directionality) {}
 }
 
+@Component({template: '<p>Pizza</p> <input> <button>Close</button>'})
+class PizzaMsgTwo {
+  constructor(public dialogRef: MatDialogRef<PizzaMsgTwo>,
+              public dialogInjector: Injector,
+              public directionality: Directionality) {}
+}
+
+@Component({template: '<p>Pizza</p> <input> <button>Close</button>'})
+class PizzaMsgThree {
+  constructor(public dialogRef: MatDialogRef<PizzaMsgThree>,
+              public dialogInjector: Injector,
+              public directionality: Directionality) {}
+}
+
 @Component({
   template: `
     <h1 mat-dialog-title>This is the title</h1>
@@ -2097,6 +2127,8 @@ const TEST_DIRECTIVES = [
   ComponentWithChildViewContainer,
   ComponentWithTemplateRef,
   PizzaMsg,
+  PizzaMsgTwo,
+  PizzaMsgThree,
   DirectiveWithViewContainer,
   ComponentWithOnPushViewContainer,
   ContentElementDialog,
@@ -2114,6 +2146,8 @@ const TEST_DIRECTIVES = [
     ComponentWithChildViewContainer,
     ComponentWithTemplateRef,
     PizzaMsg,
+    PizzaMsgTwo,
+    PizzaMsgThree,
     ContentElementDialog,
     DialogWithInjectedData,
     DialogWithoutFocusableElements,
diff --git a/src/material/dialog/dialog.ts b/src/material/dialog/dialog.ts
index a9e4d75ad845..c14927696938 100644
--- a/src/material/dialog/dialog.ts
+++ b/src/material/dialog/dialog.ts
@@ -35,6 +35,7 @@ import {startWith} from 'rxjs/operators';
 import {MatDialogConfig} from './dialog-config';
 import {MatDialogContainer, _MatDialogContainerBase} from './dialog-container';
 import {MatDialogRef} from './dialog-ref';
+import {_transitionTime} from './dialog-animations';
 
 
 /** Injection token that can be used to access the data that was passed in to a dialog. */
@@ -77,6 +78,9 @@ export abstract class _MatDialogBase<C extends _MatDialogContainerBase> implemen
   private readonly _afterOpenedAtThisLevel = new Subject<MatDialogRef<any>>();
   private _ariaHiddenElements = new Map<Element, string|null>();
   private _scrollStrategy: () => ScrollStrategy;
+  private _lastDialogOpenTime: number;
+  private _lastDialogOpenType: any;
+  private _lastDialogRef: MatDialogRef<any>;
 
   /** Keeps track of the currently-open dialogs. */
   get openDialogs(): MatDialogRef<any>[] {
@@ -144,6 +148,13 @@ export abstract class _MatDialogBase<C extends _MatDialogContainerBase> implemen
       (typeof ngDevMode === 'undefined' || ngDevMode)) {
       throw Error(`Dialog with id "${config.id}" exists already. The dialog id must be unique.`);
     }
+    // If there are open dialogs, and the last opened dialog was of the same component or template
+    // ref as the one opening now, check if we're still within the animation transition time of the
+    // previous dialog, if so, just return the MatDialogRef of the previous dialog.
+    if (this.openDialogs.length && componentOrTemplateRef === this._lastDialogOpenType &&
+        this._dialogOpenedWithinPreviousTransitionTime()) {
+      return this._lastDialogRef;
+    }
 
     const overlayRef = this._createOverlay(config);
     const dialogContainer = this._attachDialogContainer(overlayRef, config);
@@ -151,6 +162,9 @@ export abstract class _MatDialogBase<C extends _MatDialogContainerBase> implemen
                                                       dialogContainer,
                                                       overlayRef,
                                                       config);
+    this._lastDialogOpenTime = new Date().getTime();
+    this._lastDialogOpenType = componentOrTemplateRef;
+    this._lastDialogRef = dialogRef;
 
     // If this is the first dialog that we're opening, hide all the non-overlay content.
     if (!this.openDialogs.length) {
@@ -384,6 +398,16 @@ export abstract class _MatDialogBase<C extends _MatDialogContainerBase> implemen
     }
   }
 
+  /**
+   * Check if a dialog was opened within the dialog animation transition time of a previous dialog.
+   * @return true if a dialog was opened within the dialog animation transition time, false
+   *  otherwise.
+   * @docs-private
+   */
+  _dialogOpenedWithinPreviousTransitionTime(): boolean {
+    return new Date().getTime() - this._lastDialogOpenTime < _transitionTime;
+  }
+
 }
 
 /**
diff --git a/src/material/dialog/testing/shared.spec.ts b/src/material/dialog/testing/shared.spec.ts
index 284ea1c143d0..c2eefca70b83 100644
--- a/src/material/dialog/testing/shared.spec.ts
+++ b/src/material/dialog/testing/shared.spec.ts
@@ -12,6 +12,7 @@ export function runHarnessTests(
     dialogModule: typeof MatDialogModule, dialogHarness: typeof MatDialogHarness,
     dialogService: typeof MatDialog) {
   let fixture: ComponentFixture<DialogHarnessTest>;
+  let fixtureTwo: ComponentFixture<DialogHarnessTest>;
   let loader: HarnessLoader;
   let overlayContainer: OverlayContainer;
 
@@ -32,6 +33,8 @@ export function runHarnessTests(
 
     fixture = TestBed.createComponent(DialogHarnessTest);
     fixture.detectChanges();
+    fixtureTwo = TestBed.createComponent(DialogHarnessTest);
+    fixtureTwo.detectChanges();
     loader = TestbedHarnessEnvironment.documentRootLoader(fixture);
     inject([OverlayContainer], (oc: OverlayContainer) => {
       overlayContainer = oc;
@@ -57,7 +60,7 @@ export function runHarnessTests(
 
   it('should load harness for dialog with specific id', async () => {
     fixture.componentInstance.open({id: 'my-dialog'});
-    fixture.componentInstance.open({id: 'other'});
+    fixtureTwo.componentInstance.open({id: 'other'});
     let dialogs = await loader.getAllHarnesses(dialogHarness);
     expect(dialogs.length).toBe(2);
 
@@ -67,7 +70,7 @@ export function runHarnessTests(
 
   it('should be able to get id of dialog', async () => {
     fixture.componentInstance.open({id: 'my-dialog'});
-    fixture.componentInstance.open({id: 'other'});
+    fixtureTwo.componentInstance.open({id: 'other'});
     const dialogs = await loader.getAllHarnesses(dialogHarness);
     expect(await dialogs[0].getId()).toBe('my-dialog');
     expect(await dialogs[1].getId()).toBe('other');
@@ -75,7 +78,7 @@ export function runHarnessTests(
 
   it('should be able to get role of dialog', async () => {
     fixture.componentInstance.open({role: 'alertdialog'});
-    fixture.componentInstance.open({role: 'dialog'});
+    fixtureTwo.componentInstance.open({role: 'dialog'});
     fixture.componentInstance.open({role: undefined});
     const dialogs = await loader.getAllHarnesses(dialogHarness);
     expect(await dialogs[0].getRole()).toBe('alertdialog');
@@ -85,7 +88,7 @@ export function runHarnessTests(
 
   it('should be able to get aria-label of dialog', async () => {
     fixture.componentInstance.open();
-    fixture.componentInstance.open({ariaLabel: 'Confirm purchase.'});
+    fixtureTwo.componentInstance.open({ariaLabel: 'Confirm purchase.'});
     const dialogs = await loader.getAllHarnesses(dialogHarness);
     expect(await dialogs[0].getAriaLabel()).toBe(null);
     expect(await dialogs[1].getAriaLabel()).toBe('Confirm purchase.');
@@ -93,7 +96,7 @@ export function runHarnessTests(
 
   it('should be able to get aria-labelledby of dialog', async () => {
     fixture.componentInstance.open();
-    fixture.componentInstance.open({ariaLabelledBy: 'dialog-label'});
+    fixtureTwo.componentInstance.open({ariaLabelledBy: 'dialog-label'});
     const dialogs = await loader.getAllHarnesses(dialogHarness);
     expect(await dialogs[0].getAriaLabelledby()).toBe(null);
     expect(await dialogs[1].getAriaLabelledby()).toBe('dialog-label');
@@ -101,7 +104,7 @@ export function runHarnessTests(
 
   it('should be able to get aria-describedby of dialog', async () => {
     fixture.componentInstance.open();
-    fixture.componentInstance.open({ariaDescribedBy: 'dialog-description'});
+    fixtureTwo.componentInstance.open({ariaDescribedBy: 'dialog-description'});
     const dialogs = await loader.getAllHarnesses(dialogHarness);
     expect(await dialogs[0].getAriaDescribedby()).toBe(null);
     expect(await dialogs[1].getAriaDescribedby()).toBe('dialog-description');
@@ -109,7 +112,7 @@ export function runHarnessTests(
 
   it('should be able to close dialog', async () => {
     fixture.componentInstance.open({disableClose: true});
-    fixture.componentInstance.open();
+    fixtureTwo.componentInstance.open();
     let dialogs = await loader.getAllHarnesses(dialogHarness);
 
     expect(dialogs.length).toBe(2);
diff --git a/tools/public_api_guard/material/dialog.md b/tools/public_api_guard/material/dialog.md
index 31e78075329c..e12f04b72789 100644
--- a/tools/public_api_guard/material/dialog.md
+++ b/tools/public_api_guard/material/dialog.md
@@ -113,6 +113,7 @@ export abstract class _MatDialogBase<C extends _MatDialogContainerBase> implemen
     readonly afterAllClosed: Observable<void>;
     get afterOpened(): Subject<MatDialogRef<any>>;
     closeAll(): void;
+    _dialogOpenedWithinPreviousTransitionTime(): boolean;
     // (undocumented)
     _getAfterAllClosed(): Subject<void>;
     getDialogById(id: string): MatDialogRef<any> | undefined;
@@ -290,6 +291,9 @@ export class MatDialogTitle implements OnInit {
 // @public
 export function throwMatDialogContentAlreadyAttachedError(): void;
 
+// @public
+export const _transitionTime = 150;
+
 // (No @packageDocumentation comment for this package)
 
 ```