This invention provides a method, system, and apparatus for generating and manipulating the structure of user interface control hierarchies. When a web page is requested from a server by client software an initial control hierarchy configuration is generated. Upon successive requests by the client to the server, the structure of the web control hierarchy generated for the given web page may be altered, as prescribed by the specifications. The nature of those alterations can include the addition or replacement of web control sub-structures. This invention can be utilized to manipulate dynamic control hierarchies generated within a statically-generated hierarchy.