The literature on co-trimoxazole (TMP jSMX) is voluminous, but in the main it consists of research reports. The same can be said of various symposia that have appeared. This volume attempts to present the current status of this antibacterial combination in a series of topical reviews, each of which represents a comprehensive summary of a segment of the field. The editor acknowledges with appreciation the help provided by JACKIE, JENKS, LEE KUYPER, and particularly, RUTH Ross in the preparation of the Subject Index, and thanks Burroughs Wellcome Co. for providing access to library and word processing facilities. Research Triangle Park GEORGE H. HITCHINGS List of Authors Dr. J. F. ACAR, Hospital Saint-Joseph, 7, rue Pierre-Larousse, F-75674 Paris Cedex 14 Dr. N. ANAND, National Information Centre for Drugs and Pharmaceuticals, Central Drug Research Institute, Chattar Manzil, P. O. Box No. 173, Lucknow, 226001jIND Dr. D. W. BARRY, The Wellcome Research Laboratories, Burroughs Wellcome Co. , 3030 Cornwallis Road, Research Triangle Park, NC 27709jUSA Dr. R. E. BLACK, Center for Vaccine Development, University of Maryland, Division of Infectious Diseases, 29 S. Greene Street, Bressler Building, Room 404, Baltimore, MD 21201jUSA Dr. J. J. BURCHALL, Department of Microbiology, The Wellcome Research Laboratories, Burroughs Wellcome Co. , 3030 Cornwallis Road, Research Triangle Park, NC 27709jUSA Dr. S. R. M. BUSHBY, The Wellcome Research Laboratories, Burroughs Wellcome Co. , 3030 Cornwallis Road, Research Triangle Park, NC 27709jUSA Dr. M. L.