This book collects together selected papers presented at the Second Interna- tional Conference on the Structure of Surfaces (ICSOS-II). The conference was held at the Royal Thopical Institute in Amsterdam, The Netherlands, June 22-25, 1987. It was held in part to celebrate the 25th anniversary of the NEVAC (Netherlands Vacuum Society). The International Organizing Committee members were: M. A. Van Hove (Chairman) J. F. van der Veen (Vice-Chairman) W. F. van der Weg (Treasurer) D. L. Adams A. M. Bradshaw M. J. Cardillo D. J. Chadi J. E. Demuth J. Eckert G. Ertl S. Ino D. A. King B. I....