This volume contains the lectures presented at the Advanced Study Institute on "Chemistry and Chemical Engineering of Catalytic Solid Fuel Conversion for the Production of aean Synthetic Fuels" which was held at Ak~;ay, Edremit, Tiirkiye, between July 21 and August 3, 1991. The book includes 23 chapters originally written for the meeting by distinguished scientists an technologists in the field. l would like to acknowledge the contribution of each of the authors in the book. Their efforts have shed light on our understanding in coal science research and better utilization of coal. Three main subjects: structure and reactivity of coal; cleaning of coal and its products, and factors affecting environmental balance of energy usage and solutions for future, were discussed in the Institute and these are presented under six groups in the book. I hope that of great use to research workers from academic and industrial background. the book will be Many people contributed to the success of the Institute on which this volume was based. I take this occasion to thank my colleagues who lectured in the Institute, both for their efforts during the two weeks and their expertly prepared lecture notes that reached to me in time. The Institute was generously sponsored by the Scientific and Environmental Affairs Dh·ision of the NATO and their contribution is deeply acknowledged.