This volume is the result of a conference on Representation Theory of Reductive Groups held in Park City, Utah, April 16-20, 1982, under the auspices of the Department of Mathematics, University of Utah. Funding for the conference was provided by the National Science Foundation. The text includes a number of original papers together with expository articles on work already in print. It is hoped that the volume will be of use to both experts in the field and nonspecialists interested in obtaining some insight into the area. Principal organizers of the conference were Henryk Hecht, Dragan Mili~ie, and Peter Trombi. They would like to express their thanks to the National Science Foundation for their support, to the speakers for their diligence in submitting their manuscripts, and to Carla Curtis, Karen Edge, and Katherine Ruth, for typing the manuscripts which were contributed. v CONTENTS J. Arthur, Multipliers and a Paley-Wiener theorem for real reductive groups .......................................... .