The objective of the program committee of the Fifth International Symposium on Atherosclerosis was to bring together experts in many disciplines to broaden the scope of the attack on this disease and to foster interaction. Our hope was that such interaction would accelerate the eradication of the disease. The symposium achieved that objective and con tinued the tradition of the previous symposia in providing a forum for summaries of recent research developments in the study, treatment and prevention of atherosclerosis. The leading authorities and researchers in this field and in the related areas of interest have presented the newest information, concepts and ideas that have evolved in the past three years since the previous meeting in Tokyo. The most promising fields for future investigation are clearly identified, as are the nature of the controversies that persist in some highly important aspects of treatment of this disease. The appearance of these proceedings so soon after the meeting will greatly enhance the impact of the symposium on current research in atherosclerosis. The program committee is particularly indebted to the excellent response of the inves tigators for their willingness to participate in the symposium and for their successful efforts in bringing high quality to their presentations. Their cooperation in the expeditious delivery of manuscripts for this volume has been particularly gratifying. The efforts of Ms. Barbara Allen in preparing this volume bear special note.