A NATO Advanced Study Institute on "New Developments and Methods in Membrane Research and Biological Energy Transduction" was held in order to consider some of the most recent developments in membrane research methodologies and results, with particular emphasis on studies of biological energy transduction. The partic ipants in the Institute dealt with three general areas of membrane study: membrane structure (with emphasis on lipid and protein components), membrane component assembly (with particular emphasis on mitochondria and chloroplasts), and the specialized functions of certain membrane systems. This last area included discussions of topics such as drug transformation, the role of membrane electron transport in the generation of oxygen radicals, the effect of oxygen radicals on cellular homeostasis and on the structure, organization and function of the acetylcholine receptor. Lectures and posters were concerned with two central questions: what is the function of membrane structure in energy transduction and how can energy trans duction be effectively measured and assessed? This text presents the content of the major lectures and important posters presented during the Institute's program. In issuing this book, the editor hopes to convey the proceedings of the Institute to a larger audi ence and to offer a comprehensive account of those developments in membrane research that were considered on the Island of Spetsai between August 16 and August 29, 1984. L. Packer Berkeley, California February 1985 v CONTENTS I. STRUCTURE AND BIOGENSIS Membrane Structure: Neutron Diffraction and Small Angle Scattering Studies ********** 1 G.