Gordon Freeman, PhD, Professor of Medicine at Dana-Farber Cancer Institute and Harvard Medical School, is renowned for discovering the PD-L1 and PD-L2 proteins. Dr. Freeman showed that PD-L1 and PD-L2 bound to PD-1 to turn off the immune response and that blockade of PD-L1/PD-1 enhanced immune responses. He further showed that PD-L1 is highly expressed on many tumors and allows these tumors to resist immune attack. Dr. Freeman’s work led directly to the development of a successful strategy for cancer immunotherapy - blocking the PD-1-ligand interaction. Dr. Freeman has published over 400 scientific papers and holds over 90 US patents on immunotherapies. He was elected to the National Academy of Sciences and the National Academy of Inventors, is a Fellow of the AACR and SITC Academies, and has received numerous awards, including the William B. Coley Award for Distinguished Research in Tumor Immunology, the Warren Alpert Foundation Prize, and the Richard Smalley, MD, Memorial Award.