Various mobility assistants have been developed to enable the Rolland wheelchair and iWalker walker to behave intelligently in order to compensate for diminishing physical and cognitive faculties: A safety assistant ensures that the brakes are applied in time, a driving assistant avoids any obstacles and assists the user when going through doors, and the navigation assistant guides the unit along a route or can drive the user around in an autonomous manner. At the Bremen Ambient Assisted Living Lab, users can interact with these mobility assistants and the smart environment installed there. The goal is to evaluate new ambient assisted living technologies regarding their everyday usability. Various interaction modes are investigated, such as a head joystick, a touch screen, and natural language dialog.