diff --git a/src/addons/transitions/__tests__/ReactTransitionKeySet-test.js b/src/addons/transitions/__tests__/ReactTransitionKeySet-test.js
index 993ebbc6e09..8e3954a5f3a 100644
--- a/src/addons/transitions/__tests__/ReactTransitionKeySet-test.js
+++ b/src/addons/transitions/__tests__/ReactTransitionKeySet-test.js
@@ -36,8 +36,8 @@ describe('ReactTransitionKeySet', function() {
     var component = <div>{one}{two}</div>;
     expect(ReactTransitionKeySet.getChildMapping(component.props.children))
       .toEqual({
-        '{one}': one,
-        '{two}': two
+        '.$one': one,
+        '.$two': two
       });
   });
 
@@ -48,8 +48,8 @@ describe('ReactTransitionKeySet', function() {
     var two = <div key="two" />;
     var component = <div>{one}{two}</div>;
     expect(ReactTransitionKeySet.getKeySet(component.props.children)).toEqual({
-      '{one}': true,
-      '{two}': true
+      '.$one': true,
+      '.$two': true
     });
   });
 
diff --git a/src/core/ReactInstanceHandles.js b/src/core/ReactInstanceHandles.js
index 1a78bc6d9e9..b64b303ea46 100644
--- a/src/core/ReactInstanceHandles.js
+++ b/src/core/ReactInstanceHandles.js
@@ -39,7 +39,7 @@ var MAX_TREE_DEPTH = 100;
  * @internal
  */
 function getReactRootIDString(index) {
-  return SEPARATOR + 'r[' + index.toString(36) + ']';
+  return SEPARATOR + index.toString(36);
 }
 
 /**
@@ -241,7 +241,7 @@ var ReactInstanceHandles = {
    * @internal
    */
   createReactID: function(rootID, name) {
-    return rootID + SEPARATOR + name;
+    return rootID + name;
   },
 
   /**
@@ -253,8 +253,11 @@ var ReactInstanceHandles = {
    * @internal
    */
   getReactRootIDFromNodeID: function(id) {
-    var regexResult = /\.r\[[^\]]+\]/.exec(id);
-    return regexResult && regexResult[0];
+    if (id && id.charAt(0) === SEPARATOR && id.length > 1) {
+      var index = id.indexOf(SEPARATOR, 1);
+      return index > -1 ? id.substr(0, index) : id;
+    }
+    return null;
   },
 
   /**
diff --git a/src/core/ReactMultiChild.js b/src/core/ReactMultiChild.js
index dd9ce4e2e0b..58711eeae68 100644
--- a/src/core/ReactMultiChild.js
+++ b/src/core/ReactMultiChild.js
@@ -193,7 +193,7 @@ var ReactMultiChild = {
         var child = children[name];
         if (children.hasOwnProperty(name)) {
           // Inlined for performance, see `ReactInstanceHandles.createReactID`.
-          var rootID = this._rootNodeID + '.' + name;
+          var rootID = this._rootNodeID + name;
           var mountImage = child.mountComponent(
             rootID,
             transaction,
@@ -385,7 +385,7 @@ var ReactMultiChild = {
      */
     _mountChildByNameAtIndex: function(child, name, index, transaction) {
       // Inlined for performance, see `ReactInstanceHandles.createReactID`.
-      var rootID = this._rootNodeID + '.' + name;
+      var rootID = this._rootNodeID + name;
       var mountImage = child.mountComponent(
         rootID,
         transaction,
diff --git a/src/core/__tests__/ReactIdentity-test.js b/src/core/__tests__/ReactIdentity-test.js
index 3e6012b229d..c77964ef159 100644
--- a/src/core/__tests__/ReactIdentity-test.js
+++ b/src/core/__tests__/ReactIdentity-test.js
@@ -34,7 +34,7 @@ describe('ReactIdentity', function() {
     ReactMount = require('ReactMount');
   });
 
-  var idExp = /^\.r\[.+?\](.*)$/;
+  var idExp = /^\.[^.]+(.*)$/;
   function checkId(child, expectedId) {
     var actual = idExp.exec(ReactMount.getID(child));
     var expected = idExp.exec(expectedId);
@@ -55,8 +55,8 @@ describe('ReactIdentity', function() {
     React.renderComponent(instance, document.createElement('div'));
     var node = instance.getDOMNode();
     reactComponentExpect(instance).toBeDOMComponentWithChildCount(2);
-    checkId(node.childNodes[0], '.r[0].{first}[0]');
-    checkId(node.childNodes[1], '.r[0].{second}[0]');
+    checkId(node.childNodes[0], '.0.$first:0');
+    checkId(node.childNodes[1], '.0.$second:0');
   });
 
   it('should allow key property to express identity', function() {
@@ -71,10 +71,10 @@ describe('ReactIdentity', function() {
     React.renderComponent(instance, document.createElement('div'));
     var node = instance.getDOMNode();
     reactComponentExpect(instance).toBeDOMComponentWithChildCount(4);
-    checkId(node.childNodes[0], '.r[0].{apple}');
-    checkId(node.childNodes[1], '.r[0].{banana}');
-    checkId(node.childNodes[2], '.r[0].{0}');
-    checkId(node.childNodes[3], '.r[0].{123}');
+    checkId(node.childNodes[0], '.0.$apple');
+    checkId(node.childNodes[1], '.0.$banana');
+    checkId(node.childNodes[2], '.0.$0');
+    checkId(node.childNodes[3], '.0.$123');
   });
 
   it('should use instance identity', function() {
@@ -96,12 +96,12 @@ describe('ReactIdentity', function() {
     var node = instance.getDOMNode();
     reactComponentExpect(instance).toBeDOMComponentWithChildCount(3);
 
-    checkId(node.childNodes[0], '.r[0].{wrap1}');
-    checkId(node.childNodes[0].firstChild, '.r[0].{wrap1}.{squirrel}');
-    checkId(node.childNodes[1], '.r[0].{wrap2}');
-    checkId(node.childNodes[1].firstChild, '.r[0].{wrap2}.{bunny}');
-    checkId(node.childNodes[2], '.r[0].[2]');
-    checkId(node.childNodes[2].firstChild, '.r[0].[2].{chipmunk}');
+    checkId(node.childNodes[0], '.0.$wrap1');
+    checkId(node.childNodes[0].firstChild, '.0.$wrap1.$squirrel');
+    checkId(node.childNodes[1], '.0.$wrap2');
+    checkId(node.childNodes[1].firstChild, '.0.$wrap2.$bunny');
+    checkId(node.childNodes[2], '.0.2');
+    checkId(node.childNodes[2].firstChild, '.0.2.$chipmunk');
   });
 
   function renderAComponentWithKeyIntoContainer(key, container) {
@@ -116,8 +116,10 @@ describe('ReactIdentity', function() {
     expect(span1.getDOMNode()).not.toBe(null);
     expect(span2.getDOMNode()).not.toBe(null);
 
-    checkId(span1.getDOMNode(), '.r[0].{' + key + '}');
-    checkId(span2.getDOMNode(), '.r[0].[1]{' + key + '}[0]');
+    key = key.replace(/=/g, '=0');
+
+    checkId(span1.getDOMNode(), '.0.$' + key);
+    checkId(span2.getDOMNode(), '.0.1:$' + key + ':0');
   }
 
   it('should allow any character as a key, in a detached parent', function() {
diff --git a/src/core/__tests__/ReactInstanceHandles-test.js b/src/core/__tests__/ReactInstanceHandles-test.js
index 5f2048f6843..b33502aa804 100644
--- a/src/core/__tests__/ReactInstanceHandles-test.js
+++ b/src/core/__tests__/ReactInstanceHandles-test.js
@@ -154,13 +154,25 @@ describe('ReactInstanceHandles', function() {
 
   describe('getReactRootIDFromNodeID', function() {
     it('should support strings', function() {
-      var test = '.r[s_0_1][0]..[1]';
-      var expected = '.r[s_0_1]';
+      var test = '.s_0_1.0..1';
+      var expected = '.s_0_1';
       var actual = ReactInstanceHandles.getReactRootIDFromNodeID(test);
       expect(actual).toEqual(expected);
     });
   });
 
+  describe('getReactRootIDFromNodeID', function() {
+    it('should return null for invalid IDs', function() {
+      var getReactRootIDFromNodeID = (
+        ReactInstanceHandles.getReactRootIDFromNodeID
+      );
+
+      expect(getReactRootIDFromNodeID(null)).toEqual(null);
+      expect(getReactRootIDFromNodeID('.')).toEqual(null);
+      expect(getReactRootIDFromNodeID('#')).toEqual(null);
+    });
+  });
+
   describe('traverseTwoPhase', function() {
     it("should not traverse when traversing outside DOM", function() {
       var targetID = '';
diff --git a/src/core/__tests__/ReactMultiChildReconcile-test.js b/src/core/__tests__/ReactMultiChildReconcile-test.js
index 0296999223a..fb28eeb60d3 100644
--- a/src/core/__tests__/ReactMultiChildReconcile-test.js
+++ b/src/core/__tests__/ReactMultiChildReconcile-test.js
@@ -46,7 +46,9 @@ var stripEmptyValues = function(obj) {
  * here. This relies on an implementation detail of the rendering system.
  */
 var getOriginalKey = function(childName) {
-  return childName.slice('{'.length, childName.length - '}[0]'.length);
+  var match = childName.match(/^\.\$([^.]+)\:0$/);
+  expect(match).not.toBeNull();
+  return match[1];
 };
 
 /**
diff --git a/src/utils/__tests__/ReactChildren-test.js b/src/utils/__tests__/ReactChildren-test.js
index ebbfe51d039..7424bb9eb36 100644
--- a/src/utils/__tests__/ReactChildren-test.js
+++ b/src/utils/__tests__/ReactChildren-test.js
@@ -92,7 +92,7 @@ describe('ReactChildren', function() {
     expect(mappedKeys.length).toBe(1);
     expect(mappedChildren[mappedKeys[0]]).not.toBe(simpleKid);
     expect(mappedChildren[mappedKeys[0]].props.children).toBe(simpleKid);
-    expect(mappedKeys[0]).toBe('{simple}');
+    expect(mappedKeys[0]).toBe('.$simple');
   });
 
   it('should invoke callback with the right context', function() {
@@ -162,7 +162,7 @@ describe('ReactChildren', function() {
     expect(mappedKeys.length).toBe(5);
     // Keys default to indices.
     expect(mappedKeys).toEqual(
-      ['{keyZero}', '[1]', '{keyTwo}', '[3]', '{keyFour}']
+      ['.$keyZero', '.1', '.$keyTwo', '.3', '.$keyFour']
     );
 
     expect(callback).toHaveBeenCalledWith(zero, 0);
@@ -235,12 +235,12 @@ describe('ReactChildren', function() {
     expect(mappedKeys.length).toBe(6);
     // Keys default to indices.
     expect(mappedKeys).toEqual([
-      '[0]{firstHalfKey}[0]{keyZero}',
-      '[0]{firstHalfKey}[0][1]',
-      '[0]{firstHalfKey}[0]{keyTwo}',
-      '[0]{secondHalfKey}[0][0]',
-      '[0]{secondHalfKey}[0]{keyFour}',
-      '[0]{keyFive}{keyFiveInner}'
+      '.0:$firstHalfKey:0:$keyZero',
+      '.0:$firstHalfKey:0:1',
+      '.0:$firstHalfKey:0:$keyTwo',
+      '.0:$secondHalfKey:0:0',
+      '.0:$secondHalfKey:0:$keyFour',
+      '.0:$keyFive:$keyFiveInner'
     ]);
 
     expect(callback).toHaveBeenCalledWith(zero, 0);
@@ -282,15 +282,15 @@ describe('ReactChildren', function() {
       </div>
     );
 
-    var expectedForcedKeys = ['{keyZero}', '{keyOne}'];
+    var expectedForcedKeys = ['.$keyZero', '.$keyOne'];
     var mappedChildrenForcedKeys =
       ReactChildren.map(forcedKeys.props.children, mapFn);
     var mappedForcedKeys = Object.keys(mappedChildrenForcedKeys);
     expect(mappedForcedKeys).toEqual(expectedForcedKeys);
 
     var expectedRemappedForcedKeys = [
-      '{{keyZero^C}{giraffe}',
-      '{{keyOne^C}[0]'
+      '.$=1$keyZero:$giraffe',
+      '.$=1$keyOne:0'
     ];
     var remappedChildrenForcedKeys =
       ReactChildren.map(mappedChildrenForcedKeys, mapFn);
diff --git a/src/utils/__tests__/sliceChildren-test.js b/src/utils/__tests__/sliceChildren-test.js
index 1b3bfb26ecd..cac790463f1 100644
--- a/src/utils/__tests__/sliceChildren-test.js
+++ b/src/utils/__tests__/sliceChildren-test.js
@@ -68,9 +68,9 @@ describe('sliceChildren', function() {
     ];
     var children = renderAndSlice(fullSet, 0);
     expect(children).toEqual({
-      '{A}': fullSet[0],
-      '{B}': fullSet[1],
-      '{C}': fullSet[2]
+      '.$A': fullSet[0],
+      '.$B': fullSet[1],
+      '.$C': fullSet[2]
     });
   });
 
@@ -82,8 +82,8 @@ describe('sliceChildren', function() {
     ];
     var children = renderAndSlice(fullSet, 1);
     expect(children).toEqual({
-      '{B}': fullSet[1],
-      '{C}': fullSet[2]
+      '.$B': fullSet[1],
+      '.$C': fullSet[2]
     });
   });
 
@@ -96,7 +96,7 @@ describe('sliceChildren', function() {
     ];
     var children = renderAndSlice(fullSet, 1, 2);
     expect(children).toEqual({
-      '{B}': fullSet[1]
+      '.$B': fullSet[1]
     });
   });
 
@@ -112,7 +112,7 @@ describe('sliceChildren', function() {
       .instance();
 
     expect(rendered.props.children).toEqual({
-      '[1]': b
+      '.1': b
     });
   });
 
diff --git a/src/utils/__tests__/traverseAllChildren-test.js b/src/utils/__tests__/traverseAllChildren-test.js
index 7386a5d6acd..0b66e04d458 100644
--- a/src/utils/__tests__/traverseAllChildren-test.js
+++ b/src/utils/__tests__/traverseAllChildren-test.js
@@ -43,7 +43,7 @@ describe('traverseAllChildren', function() {
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       simpleKid,
-      '{simple}',
+      '.$simple',
       0
     );
     expect(traverseContext.length).toEqual(1);
@@ -62,7 +62,7 @@ describe('traverseAllChildren', function() {
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       simpleKid,
-      '[0]',
+      '.0',
       0
     );
     expect(traverseContext.length).toEqual(1);
@@ -81,7 +81,7 @@ describe('traverseAllChildren', function() {
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       simpleKid,
-      '[0]',
+      '.0',
       0
     );
     expect(traverseContext.length).toEqual(1);
@@ -114,21 +114,21 @@ describe('traverseAllChildren', function() {
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       zero,
-      '{keyZero}',
+      '.$keyZero',
       0
     );
-    expect(traverseFn).toHaveBeenCalledWith(traverseContext, one, '[1]', 1);
+    expect(traverseFn).toHaveBeenCalledWith(traverseContext, one, '.1', 1);
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       two,
-      '{keyTwo}',
+      '.$keyTwo',
       2
     );
-    expect(traverseFn).toHaveBeenCalledWith(traverseContext, three, '[3]', 3);
+    expect(traverseFn).toHaveBeenCalledWith(traverseContext, three, '.3', 3);
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       four,
-      '{keyFour}',
+      '.$keyFour',
       4
     );
   });
@@ -171,38 +171,38 @@ describe('traverseAllChildren', function() {
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       zero,
-      '[0]{firstHalfKey}[0]{keyZero}',
+      '.0:$firstHalfKey:0:$keyZero',
       0
     );
 
     expect(traverseFn)
-      .toHaveBeenCalledWith(traverseContext, one, '[0]{firstHalfKey}[0][1]', 1);
+      .toHaveBeenCalledWith(traverseContext, one, '.0:$firstHalfKey:0:1', 1);
 
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       two,
-      '[0]{firstHalfKey}[0]{keyTwo}',
+      '.0:$firstHalfKey:0:$keyTwo',
       2
     );
 
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       three,
-      '[0]{secondHalfKey}[0][0]',
+      '.0:$secondHalfKey:0:0',
       3
     );
 
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       four,
-      '[0]{secondHalfKey}[0]{keyFour}',
+      '.0:$secondHalfKey:0:$keyFour',
       4
     );
 
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       five,
-      '[0]{keyFive}{keyFiveInner}',
+      '.0:$keyFive:$keyFiveInner',
       5
     );
   });
@@ -228,13 +228,13 @@ describe('traverseAllChildren', function() {
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       zeroForceKey,
-      '{keyZero}',
+      '.$keyZero',
       0
     );
     expect(traverseFn).toHaveBeenCalledWith(
       traverseContext,
       oneForceKey,
-      '{keyOne}',
+      '.$keyOne',
       1
     );
   });
diff --git a/src/utils/traverseAllChildren.js b/src/utils/traverseAllChildren.js
index 0406ad268cb..8b935019e83 100644
--- a/src/utils/traverseAllChildren.js
+++ b/src/utils/traverseAllChildren.js
@@ -18,10 +18,14 @@
 
 "use strict";
 
+var ReactInstanceHandles = require('ReactInstanceHandles');
 var ReactTextComponent = require('ReactTextComponent');
 
 var invariant = require('invariant');
 
+var SEPARATOR = ReactInstanceHandles.SEPARATOR;
+var SUBSEPARATOR = ':';
+
 /**
  * TODO: Test that:
  * 1. `mapChildren` transforms strings and numbers into `ReactTextComponent`.
@@ -31,12 +35,12 @@ var invariant = require('invariant');
  */
 
 var userProvidedKeyEscaperLookup = {
-  '^': '^X',
-  '.': '^D',
-  '}': '^C'
+  '=': '=0',
+  '.': '=1',
+  ':': '=2'
 };
 
-var userProvidedKeyEscapeRegex = /[.^}]/g;
+var userProvidedKeyEscapeRegex = /[=.:]/g;
 
 function userProvidedKeyEscaper(match) {
   return userProvidedKeyEscaperLookup[match];
@@ -55,7 +59,7 @@ function getComponentKey(component, index) {
     return wrapUserProvidedKey(component.props.key);
   }
   // Implicit key determined by the index in the set
-  return '[' + index + ']';
+  return index.toString(36);
 }
 
 /**
@@ -79,7 +83,7 @@ function escapeUserProvidedKey(text) {
  * @return {string}
  */
 function wrapUserProvidedKey(key) {
-  return '{' + escapeUserProvidedKey(key) + '}';
+  return '$' + escapeUserProvidedKey(key);
 }
 
 /**
@@ -97,7 +101,11 @@ var traverseAllChildrenImpl =
     if (Array.isArray(children)) {
       for (var i = 0; i < children.length; i++) {
         var child = children[i];
-        var nextName = nameSoFar + getComponentKey(child, i);
+        var nextName = (
+          nameSoFar +
+          (nameSoFar ? SUBSEPARATOR : SEPARATOR) +
+          getComponentKey(child, i)
+        );
         var nextIndex = indexSoFar + subtreeCount;
         subtreeCount += traverseAllChildrenImpl(
           child,
@@ -112,8 +120,9 @@ var traverseAllChildrenImpl =
       var isOnlyChild = nameSoFar === '';
       // If it's the only child, treat the name as if it was wrapped in an array
       // so that it's consistent if the number of children grows
-      var storageName = isOnlyChild ? getComponentKey(children, 0) : nameSoFar;
-      if (children === null || children === undefined || type === 'boolean') {
+      var storageName =
+        isOnlyChild ? SEPARATOR + getComponentKey(children, 0) : nameSoFar;
+      if (children == null || type === 'boolean') {
         // All of the above are perceived as null.
         callback(traverseContext, null, storageName, indexSoFar);
         subtreeCount = 1;
@@ -132,8 +141,8 @@ var traverseAllChildrenImpl =
               subtreeCount += traverseAllChildrenImpl(
                 children[key],
                 (
-                  nameSoFar +
-                  wrapUserProvidedKey(key) +
+                  nameSoFar + (nameSoFar ? SUBSEPARATOR : SEPARATOR) +
+                  wrapUserProvidedKey(key) + SUBSEPARATOR +
                   getComponentKey(children[key], 0)
                 ),
                 indexSoFar + subtreeCount,