Alexander Rudensky is Chairman of the Immunology Program and Director of the Ludwig Center for Cancer Immunotherapy at Memorial Sloan-Kettering Cancer Center (MSKCC), an Investigator with the Howard Hughes Medical Institute, and a Tri-Institutional Professor at MSKCC, the Rockefeller University and Cornell University. Prior to his joining MSKCC, he was Professor of Immunology at the University of Washington School of Medicine, Seattle. Dr. Rudensky received his Ph.D. degree from the Gabrichevsky Research Institute of Epidemiology and Microbiology, Moscow and postdoctoral training at Yale University Medical School with the late Dr. Charles A. Janeway, Jr. Currently, Dr. Rudensky's research is focused on the differentiation of regulatory T lymphocytes, and their role in the immune responses. His laboratory demonstrated a role for the transcription factor Foxp3 as a Treg cell lineage specification factor; his studies revealed an essential role for these cells as life-long "guardians" of immune homeostasis and key mechanisms of their differentiation and function. Dr. Rudensky's work provided important insights into the fundamental role for regulatory T cells in immunological tolerance and in a variety of processes and pathologies including autoimmunity, allergy, transplantation, immunity to infections, pregnancy, tissue repair, and cancer.