In this R13 proposal for NIH support of a single scientific meeting, we will present a detailed outline for the 19th Annual International Natural Killer Cell Workshop/7th Annual Meeting of the Society for Natural Immunity to be held October 7-9, 2001 at The Caribe Hilton Hotel in San Juan, Puerto Rico, a Commonwealth Island of the United States of America. The participants will consist of M.D., Ph.D., and M.D.-Ph.D. basic and clinical scientists interested in innate immunity, natural killer cell biology, and clinical applications of natural killer cell biology. The meeting is generally attended by 150-250 participants that include virtually all the leaders in the field of natural killer cell biology as well as pre-doctoral and post-doctoral students that comprise approximately 50 percent of the attendees. The goals of the meeting are to: 1) bring together senior and junior level researchers in the field of NK cell biology, and also those in related areas of non- adaptive immunity; 2) provide a forum for presenting and discussing the newest and most significant developments in select areas of non-adaptive immunity and T/NK leukemia; 3) provide a special opportunity for a select group of students and faculty of Hispanic origin from Puerto Rico to participate in a pre- meeting mini-course on NK cell biology and to participate in the meeting itself; 4) determine future directions in the field both in terms of basic research and clinical applications. The topics include: NK Differentiation, Nk/NKT Regulation, Clinical and Basic Aspects of NK Biology, NK Cell Signaling, NK Cell Receptor Expression and Function, and three workshops led by the leaders in the field of NK cell biology. Finally, there will be a distinguished lecture, delivered by Dr. Thomas Waldmann of the NIH on T-NK Cell Leukemia, reviewing the basic and clinical aspects. Through a formal collaboration with the University of Puerto Rico, there will be a series of pre-meeting lectures at the University on innate immunity by the 3 program organizers, and a concerted effort to bring minority Hispanic pre-doctoral and post-doctoral students to the meeting and to the U.S. for post-doctoral training. Funds are requested to support the latter effort as well as support for a fraction of the invited speakers and program planner.