diff --git a/src/browser/ReactComponentBrowserEnvironment.js b/src/browser/ReactComponentBrowserEnvironment.js
index 12e4b593169..39c290eb6f0 100644
--- a/src/browser/ReactComponentBrowserEnvironment.js
+++ b/src/browser/ReactComponentBrowserEnvironment.js
@@ -20,6 +20,7 @@
 
 "use strict";
 
+var DOMNodeTypes = require('DOMNodeTypes');
 var ReactDOMIDOperations = require('ReactDOMIDOperations');
 var ReactMarkupChecksum = require('ReactMarkupChecksum');
 var ReactMount = require('ReactMount');
@@ -30,10 +31,6 @@ var getReactRootElementInContainer = require('getReactRootElementInContainer');
 var invariant = require('invariant');
 
 
-var ELEMENT_NODE_TYPE = 1;
-var DOC_NODE_TYPE = 9;
-
-
 /**
  * Abstracts away all functionality of `ReactComponent` requires knowledge of
  * the browser context.
@@ -66,8 +63,9 @@ var ReactComponentBrowserEnvironment = {
     function(markup, container, shouldReuseMarkup) {
       invariant(
         container && (
-          container.nodeType === ELEMENT_NODE_TYPE ||
-            container.nodeType === DOC_NODE_TYPE
+          container.nodeType === DOMNodeTypes.ELEMENT ||
+            container.nodeType === DOMNodeTypes.DOC ||
+            container.nodeType === DOMNodeTypes.SHADOW_ROOT
         ),
         'mountComponentIntoNode(...): Target container is not valid.'
       );
@@ -79,7 +77,7 @@ var ReactComponentBrowserEnvironment = {
           return;
         } else {
           invariant(
-            container.nodeType !== DOC_NODE_TYPE,
+            container.nodeType !== DOMNodeTypes.DOC,
             'You\'re trying to render a component to the document using ' +
             'server rendering but the checksum was invalid. This usually ' +
             'means you rendered a different component type or props on ' +
@@ -106,7 +104,7 @@ var ReactComponentBrowserEnvironment = {
       }
 
       invariant(
-        container.nodeType !== DOC_NODE_TYPE,
+        container.nodeType !== DOMNodeTypes.DOC,
         'You\'re trying to render a component to the document but ' +
           'you didn\'t use server rendering. We can\'t do this ' +
           'without using server rendering due to cross-browser quirks. ' +
diff --git a/src/browser/ReactDOMComponent.js b/src/browser/ReactDOMComponent.js
index 6ac4177b0c9..054589a4d8f 100644
--- a/src/browser/ReactDOMComponent.js
+++ b/src/browser/ReactDOMComponent.js
@@ -20,6 +20,7 @@
 "use strict";
 
 var CSSPropertyOperations = require('CSSPropertyOperations');
+var DOMNodeTypes = require('DOMNodeTypes');
 var DOMProperty = require('DOMProperty');
 var DOMPropertyOperations = require('DOMPropertyOperations');
 var ReactBrowserComponentMixin = require('ReactBrowserComponentMixin');
@@ -44,8 +45,6 @@ var CONTENT_TYPES = {'string': true, 'number': true};
 
 var STYLE = keyOf({style: null});
 
-var ELEMENT_NODE_TYPE = 1;
-
 /**
  * @param {?object} props
  */
@@ -68,7 +67,7 @@ function assertValidProps(props) {
 function putListener(id, registrationName, listener, transaction) {
   var container = ReactMount.findReactContainerForID(id);
   if (container) {
-    var doc = container.nodeType === ELEMENT_NODE_TYPE ?
+    var doc = container.nodeType === DOMNodeTypes.ELEMENT ?
       container.ownerDocument :
       container;
     listenTo(registrationName, doc);
diff --git a/src/browser/ReactMount.js b/src/browser/ReactMount.js
index 1075f15cb63..4412c8d2c46 100644
--- a/src/browser/ReactMount.js
+++ b/src/browser/ReactMount.js
@@ -18,6 +18,7 @@
 
 "use strict";
 
+var DOMNodeTypes = require('DOMNodeTypes');
 var DOMProperty = require('DOMProperty');
 var ReactEventEmitter = require('ReactEventEmitter');
 var ReactInstanceHandles = require('ReactInstanceHandles');
@@ -33,9 +34,6 @@ var SEPARATOR = ReactInstanceHandles.SEPARATOR;
 var ATTR_NAME = DOMProperty.ID_ATTRIBUTE_NAME;
 var nodeCache = {};
 
-var ELEMENT_NODE_TYPE = 1;
-var DOC_NODE_TYPE = 9;
-
 /** Mapping from reactRootID to React component instance. */
 var instancesByReactRootID = {};
 
@@ -269,8 +267,9 @@ var ReactMount = {
   _registerComponent: function(nextComponent, container) {
     invariant(
       container && (
-        container.nodeType === ELEMENT_NODE_TYPE ||
-        container.nodeType === DOC_NODE_TYPE
+        container.nodeType === DOMNodeTypes.ELEMENT ||
+        container.nodeType === DOMNodeTypes.DOC ||
+        container.nodeType === DOMNodeTypes.SHADOW_ROOT
       ),
       '_registerComponent(...): Target container is not a DOM element.'
     );
@@ -444,7 +443,7 @@ var ReactMount = {
   unmountComponentFromNode: function(instance, container) {
     instance.unmountComponent();
 
-    if (container.nodeType === DOC_NODE_TYPE) {
+    if (container.nodeType === DOMNodeTypes.DOC) {
       container = container.documentElement;
     }
 
diff --git a/src/browser/dom/DOMNodeTypes.js b/src/browser/dom/DOMNodeTypes.js
new file mode 100644
index 00000000000..a2c4e7dfae2
--- /dev/null
+++ b/src/browser/dom/DOMNodeTypes.js
@@ -0,0 +1,36 @@
+/**
+ * Copyright 2013-2014 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * @providesModule DOMNodeTypes
+ * @typechecks static-only
+ */
+
+/*jslint evil: true */
+
+"use strict";
+
+/**
+ * A collection of `nodeType` values.
+ *
+ * @type {object}
+ * @internal
+ */
+var DOMNodeTypes = {
+  ELEMENT: 1,
+  DOC: 9,
+  SHADOW_ROOT: 11
+};
+
+module.exports = DOMNodeTypes;
diff --git a/src/browser/getReactRootElementInContainer.js b/src/browser/getReactRootElementInContainer.js
index 3ecf18194dc..ff8d88c6b55 100644
--- a/src/browser/getReactRootElementInContainer.js
+++ b/src/browser/getReactRootElementInContainer.js
@@ -18,7 +18,7 @@
 
 "use strict";
 
-var DOC_NODE_TYPE = 9;
+var DOMNodeTypes = require('DOMNodeTypes');
 
 /**
  * @param {DOMElement|DOMDocument} container DOM element that may contain
@@ -30,7 +30,7 @@ function getReactRootElementInContainer(container) {
     return null;
   }
 
-  if (container.nodeType === DOC_NODE_TYPE) {
+  if (container.nodeType === DOMNodeTypes.DOC) {
     return container.documentElement;
   } else {
     return container.firstChild;
diff --git a/src/browser/putDOMComponentListener.js b/src/browser/putDOMComponentListener.js
index bad4387e7cc..5674477a0bb 100644
--- a/src/browser/putDOMComponentListener.js
+++ b/src/browser/putDOMComponentListener.js
@@ -18,17 +18,16 @@
 
 "use strict";
 
+var DOMNodeTypes = require('DOMNodeTypes');
 var ReactEventEmitter = require('ReactEventEmitter');
 var ReactMount = require('ReactMount');
 
 var listenTo = ReactEventEmitter.listenTo;
 
-var ELEMENT_NODE_TYPE = 1;
-
 function putDOMComponentListener(id, registrationName, listener) {
   var container = ReactMount.findReactContainerForID(id);
   if (container) {
-    var doc = container.nodeType === ELEMENT_NODE_TYPE ?
+    var doc = container.nodeType === DOMNodeTypes.ELEMENT ?
       container.ownerDocument :
       container;
     listenTo(registrationName, doc);