The hypermedia domain is currently receiving much attention, mostly due to the new generation of open systems, i.e., those that allow the connection among applications in the same or different machines (intranets) or those that publish the interface of an application in a WWW's browser. However, current applications in this domain are not taking profit of all benefits that characterize hypermedia applications, and maintenance is very difficult to achieve. Building large hypermedia applications is a hard task, and although there exist many hypermedia design methodologies [Schwabe96, Izakowitz95], we also need design patterns that convey the expertise in the domain. We present in this paper three pattern systems intended to provide guidance for different aspects of hypermedia applications; the first one is concerned with the development of software support for hypermedia in the context of object-oriented applications; the second one deals with organizing the navigational structures in a clear and meaningful way for intended readers and the third one comprises patterns for building effective graphical interfaces.