This grant in the Organic and Macromolecular Chemistry Program will support a series of three annual "Workshops on Reactive Intermediates." These workshops have the dual purposes of (1) providing an effective forum for informal discussion by active scientists of current research in topical areas of organic dynamics, and (2) assisting the Program staff in identifying areas of research in organic dynamics which require incorporation into the Program's long-range planning. Each workshop will bring together approximately 18 active scientists from around the United States for discussions of current research in mechanisms of organic chemical reactions, with an emphasis on critical evaluation of research in progress. The informal discussion format is intended to stimulate challenge and criticism, to facilitate the development of collaborative research approaches to common problems, and to prevent unproductive duplicative efforts. The participants are drawn widely from the community of physical, organic, and organometallic chemists working on the chemistry of reactive intermediates, and a particular effort is made to incorporate young investigators, women and minority scientists into the mainstream of research activity in the areas of organic dynamics. The topics chosen for discussion are selected to complement, not compete with, other established and more formal conferences.