The objective of the Training Program in Immunology at Sloan-Kettering Institution is to provide junior postdoctoral fellows a solid foundation in the field of Immunology and to direct their interests towards important aspects of the immune system and its response to infectious agents, self antigens, and cancer. Four postdoctoral positions are requested for this competitive renewal, which is unchanged from the past grant period. The duration of training will be 2 years. The Training Program provides trainees with the intensive training, resources and experience necessary for them to develop successful careers in academia, government, and industry as independent researchers and leaders. Areas of research training cover lymphocyte development and biology, signaling, innate immunity, infectious immunity, transplantation immunity and cancer immunology. The objectives of the Training Program are achieved by providing a structured environment with intensive involvement in immunology research, further strengthened by attendance at weekly seminars and research-in-progress meetings, monthly research colloquia and translational research seminars and an annual retreat. Trainees are also expected to participate in advanced courses covering contemporary topics of immunology and workshops on bioinformatics and grant writing skills. The major part of the training comes from the research experience under the tutelage of preceptors who are engaged in cutting-edge immunology research, with bearing on lymphocyte biology, cell signaling and transcription, innate immunity, infectious diseases, autoimmune diseases, transplantation and cancer. Trainees can also take advantage of the many interdisciplinary collaborations between members of the Immunology Training Program and respected outside scientists, both locally and nationally.