This work is the fifth volume in an evolving series known collectively as "Studies in Perception and Action". It features papers presented at the Tenth International Conference on Perception and Action held in Edinburgh, Scotland in August of 1999. This series provides an insight into the evolution of research on the ecological approach to perception and action. Each volume presents new research and gives a special place to younger scientists whose work contains the seeds which will, in due course, determine the future growth and direction of the discipline. "Studies in Perception and Action" thus offers the reader not just a cross-section of leading research at a given point in time, but a mini-history of ecological psychology and its development. In this regard it is already notable how many of the "younger scientists" in the 1991 volume have become, in 1999, leading figures of the day.