[en] A subject of considerable interest to most geologists is how ore deposits are formed. The new methods include the investigation of fluid and gas inclusions within minerals in and around the deposits, the study of trace elements and isotopes, and improved microscopic techniques. The facts that have emerged have in some cases required a reconsideration of previous concepts and theories, thus providing a more scientific basis to our understanding of the ore deposits. A number of these different types of deposit are of economic interest as sources of uranium and are in production. Major types now recognized include the surficial types, including calcretes and bog types; sandstone impregnations; quartz pebble conglomerates; unconformity types; classical vein types, including pegmatites; and disseminated types in magmatic rocks. Improving our understanding of the metallogenesis of uranium deposits can significantly enhance the technological basis for exploration for new deposits and improve our ability to evaluate known and undiscovered resources. This can lead to shortened lead times and reduced costs for the discovery and production of uranium from new sources and provide additional assurance of an adequate supply of uranium to meet the long term needs for fuelling nuclear power reactors. A Technical Committee Meeting was organized by the IAEA to bring together current knowledge on the processes involved in the formation of the various types of uranium deposit in Vienna, Austria, from 9 to 12 March 1987, and involved some 60 participants from some 20 countries and two international organizations. During the meeting three panels were organized to discuss and report on specific topics: the formation of uranium deposits; the use of metallogenic concepts in uranium exploration; and deposit classification schemes and models. The technical papers, together with the discussions and the panel reports, make up this volume. Refs, figs and tabs