An R&D project to build a series of intelligent autonomous wheelchairs is discussed. A standardized autonomy management system that can be installed on commercially available well-engineered power chairs has been developed and tested. A behavior-based approach was used to establish sufficient on-board autonomy at minimal cost and material usage, while achieving high efficiency, maximum safety, Iransparency in appearance, and extendability. So far, the add-on system has been installed and tried on two power wheelchair models. Initial results are highly encouraging.