Flexibility in interface development

Two systems that employ intelligent user interfaces as front ends have been developed using Focus technology. The two systems, while addressing essentially the same user tasks, were built for different user populations, they had different development contexts, and produced as a result different systems. The discussion highlights the problems posed by these diverse development and user contexts and shows how the Focus project´s architecture and toolkit has met these challenges. The paper looks at the organisational context of the two developments and then discusses the two systems in the context of the system architectures and interfaces