Partial support is provided to the Fifth Trilateral Symposium on Catalysis to be held in Evanston, Illinois, on June 27-29, 1991. The title of the symposium is "Molecular Interactions in Heterogeneous Catalysis". This funding will provide for attendence at the symposium of American researchers who would otherwise be unalbe to attend, especially younger investigators. This series of symposia, rotating among the three countries (U.S., China, and Japan) has developed into the major trans- Pacific forum for catalysis, and is a principal source for information on Japanese activity in the field. //