A method, computer program product and system for handing messages in a Web application. Messages in a Web application may be handled by inserting a writeable block in a window in a first page of the Web application where the writeable block for receiving a message may be generated by the Web application. In a second page of the Web application, a message script may be inserted if a message is generated by the Web application for display in response to an execution of the second page. In response to the message script, the message handler is invoked.