A NATO Advanced Studies Institute was held June 12-23, 1978, at the University of Wisconsin in Madison, Wisconsin. It was a topical Institute in theoretical nuclear physics and had the some­ what novel feature of focussing not on a single topic but on two closely allied ones: pion-nucleus and heavy-ion physics. These two fields. both dedicated to the investigation of short-wave­ length properties of nuclei, have many techniques and concepts in cornmon, and essentially become one in the topic of relativistic heavy-ion physics. The purpose of including both in a single Institute was to encourage the practitioners in each of these fields to learn from those in the other; to judge from the liveli­ ness of the questioning which ensued, the purpose was well-served indeed. Because the Institute was viewed as one which served both educational and research ends, the lecturers took particular pains to develop their subjects in a careful, coherent sequence. The result is a compendium of advanced techniques and current results in these two rapidly-expanding fields of nuclear theory which should serve interested physicists as an ideal introduction to the fields. In addition to the support provided by the Scientific Affairs Division of NATO, substantial financial assistance was provided by the U. S. National Science Foundation and the Graduate School of the University of Wisconsin.