In this project ("Mechanisms of Transition Metal- Catalyzed Reactions in Hydrocarbons"), which is jointly supported by the Organic Dynamics Program of the Chemistry Division and the Polymers Program of the Division of Materials Research, Professor Robert H.Grubbs of the Chemistry Department at the California Institute of Technology will study the mechanisms for polymer synthesis with organometallic reagents. The project is designed to provide the fundamental techniques and the mechanistic understanding that is required to exploit new catalysts that have been uncovered over the past few years for synthesizing macromolecular systems. This is project is fundamental and multidisciplinary in its scope. The major topics being investigated deal extensively with further elaboration of "ROMP" polymers and will include studies on anionic initiation, macromer synthesis, tacticity control, photochemical initiation, ruthenium chemistry in aqueous media, various titanium and zirconium systems, and dual Schrock initiators.