Pass a URLRequest object to the navigateToURL()
<?xml version="1.0"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"> <mx:Script> import flash.net.*; public function openNewWindow(event:MouseEvent):void { var u:URLRequest = new URLRequest("http://www.adobe.com/flex"); navigateToURL(u,"_blank"); } </mx:Script> <mx:Button label="Open New Window" click="openNewWindow(event)" /> </mx:Application>