1. A method for efficiently encoding navigational state in a Portal, wherein said Portal is running in a server system, wherein said server system includes a communication component which allows communication between said Portal and client's browser via a communication channel, wherein said Portal determines the layout of the requested Portal page, invokes rendering of the various page elements belonging to said Portal page, and transmits said Portal page to the client's browser for displaying, wherein at least one page element of said Portal page provides an URL functionality for initiating rendering a new page or new page element by said Portal, wherein each user interaction by clicking said URL at said page element generates a new navigational state at said Portal side, wherein the latest navigational state describes the current view of said Portal as the result of all previous navigational interactions of a particular client, wherein said at least latest navigational state is saved by said Portal, wherein in response to a client request for a new Portal page said method is characterized by the steps of: creating a base navigational state which describes that part of the latest navigational state that is identical across all URLs of said new Portal page, creating for each URL included in said new Portal page to be rendered and not contained in said base navigational state an URL specific delta navigational state which describes the state transition of said specific URL when said specific URL is invoked, encoding said base navigational state into the header of said Portal page once, encoding each URL specific delta navigational state into its assigned URL being part of said Portal page, and generating and transmitting a response to said client's browser including said new Portal page for displaying by said client's browser.