There are striking parallels between ecological psychology and new trends in robotics and computer vision, particu?larly regarding how agents interact with the environment. W e present some ideas from ecological psychology, in?cluding control laws using optical flow, affordances and action modes, and describe our implementation of these concepts in a small mobile robot which can avoid obstacles and play tag solely using optical flow. This work ties in with those of others arguing for a methodological approach in robotics which foregoes a cen?tral model/planner. Ecological psychology may not only contribute to robotics, but robotic implementations in turn provide a test bed for ecological principles and sources of ideas which could be tested in animals and humans.