This book contains the papers presented at the International Workshop on Visual Fonn, held in Capri (Italy) on May 27-30, 1991. The workshop, sponsored by the International Association for Pattern Recognition (!APR), has been jointly organized by the Dipartimento di Infonnatica e Sisternistica of the University of Naples and the Istituto di Cibemetica of the National Research Council of Italy, and has focussed on Shape. Shape is a distinctive feature of most patterns, so that recognition can often be attained through shape discrimination. The organizers of the workshop shared the general feeling manifested by researchers, that it was time for holding a meeting exclusively devoted to a feature so crucial for both human and machine perception. During this meeting, problems and prospects in the field of 2D and 3D shape analysis could be discussed extensively, so as to provide an effective, updated picture of the current research activity in which shape plays a central role. Indeed, many highly qualified researchers in the field positively reacted to the Call for Papers.