This is a commemoration volume to honour Professor M. Veltman on the occasion of his 60th birthday. It contains articles on gauge field theories, a subject to which Professor Veltman has made many important and seminal contributions. Some of the contributions are based on invited talks given at the Conference held in Ann Arbor, Michigan, May 16-18 1991. The articles in the book cover a wide range of topics from formal and phenomenological to the experimental aspects of gauge theories.