diff --git a/tests/unit/core/selector.js b/tests/unit/core/selector.js
index 14f1de70e..dee24809e 100644
--- a/tests/unit/core/selector.js
+++ b/tests/unit/core/selector.js
@@ -1,7 +1,8 @@
 define( [
 	"jquery",
 	"ui/core",
-	"ui/data"
+	"ui/data",
+	"ui/focusable"
 ], function( $ ) {
 
 module( "core - selectors" );
diff --git a/ui/core.js b/ui/core.js
index 1072e89f1..a0931dffa 100644
--- a/ui/core.js
+++ b/ui/core.js
@@ -22,6 +22,7 @@
 			"jquery",
 			"./data",
 			"./disable-selection",
+			"./focusable",
 			"./version"
 		], factory );
 	} else {
@@ -180,44 +181,11 @@ $.fn.extend( {
 	}
 } );
 
-// selectors
-function focusable( element, hasTabindex ) {
-	var map, mapName, img,
-		nodeName = element.nodeName.toLowerCase();
-	if ( "area" === nodeName ) {
-		map = element.parentNode;
-		mapName = map.name;
-		if ( !element.href || !mapName || map.nodeName.toLowerCase() !== "map" ) {
-			return false;
-		}
-		img = $( "img[usemap='#" + mapName + "']" )[ 0 ];
-		return !!img && visible( img );
-	}
-	return ( /^(input|select|textarea|button|object)$/.test( nodeName ) ?
-		!element.disabled :
-		"a" === nodeName ?
-			element.href || hasTabindex :
-			hasTabindex ) &&
-		// the element and all of its ancestors must be visible
-		visible( element );
-}
-
-function visible( element ) {
-	return $.expr.filters.visible( element ) &&
-		!$( element ).parents().addBack().filter( function() {
-			return $.css( this, "visibility" ) === "hidden";
-		} ).length;
-}
-
 $.extend( $.expr[ ":" ], {
-	focusable: function( element ) {
-		return focusable( element, $.attr( element, "tabindex" ) != null );
-	},
-
 	tabbable: function( element ) {
 		var tabIndex = $.attr( element, "tabindex" ),
 			hasTabindex = tabIndex != null;
-		return ( !hasTabindex || tabIndex >= 0 ) && focusable( element, hasTabindex );
+		return ( !hasTabindex || tabIndex >= 0 ) && $.ui.focusable( element, hasTabindex );
 	}
 } );
 
diff --git a/ui/dialog.js b/ui/dialog.js
index 11ff77c6b..4dbf2ab34 100644
--- a/ui/dialog.js
+++ b/ui/dialog.js
@@ -26,6 +26,7 @@
 			"./widget",
 			"./button",
 			"./draggable",
+			"./focusable",
 			"./mouse",
 			"./position",
 			"./resizable",
diff --git a/ui/focusable.js b/ui/focusable.js
new file mode 100644
index 000000000..b6e86e062
--- /dev/null
+++ b/ui/focusable.js
@@ -0,0 +1,64 @@
+/*!
+ * jQuery UI Focusable @VERSION
+ * http://jqueryui.com
+ *
+ * Copyright jQuery Foundation and other contributors
+ * Released under the MIT license.
+ * http://jquery.org/license
+ */
+
+//>>label: focusable
+//>>group: Core
+//>>description: Selects elements which can be focused.
+//>>docs: http://api.jqueryui.com/focusable-selector/
+
+( function( factory ) {
+	if ( typeof define === "function" && define.amd ) {
+
+		// AMD. Register as an anonymous module.
+		define( [ "jquery", "./version" ], factory );
+	} else {
+
+		// Browser globals
+		factory( jQuery );
+	}
+} ( function( $ ) {
+
+// selectors
+$.ui.focusable = function( element, hasTabindex ) {
+	var map, mapName, img,
+		nodeName = element.nodeName.toLowerCase();
+	if ( "area" === nodeName ) {
+		map = element.parentNode;
+		mapName = map.name;
+		if ( !element.href || !mapName || map.nodeName.toLowerCase() !== "map" ) {
+			return false;
+		}
+		img = $( "img[usemap='#" + mapName + "']" )[ 0 ];
+		return !!img && visible( img );
+	}
+	return ( /^(input|select|textarea|button|object)$/.test( nodeName ) ?
+		!element.disabled :
+		"a" === nodeName ?
+			element.href || hasTabindex :
+			hasTabindex ) &&
+		// the element and all of its ancestors must be visible
+		visible( element );
+};
+
+function visible( element ) {
+	return $.expr.filters.visible( element ) &&
+		!$( element ).parents().addBack().filter( function() {
+			return $.css( this, "visibility" ) === "hidden";
+		} ).length;
+}
+
+$.extend( $.expr[ ":" ], {
+	focusable: function( element ) {
+		return $.ui.focusable( element, $.attr( element, "tabindex" ) != null );
+	}
+} );
+
+return $.ui.focusable;
+
+} ) );