James P. Allison (born 7 August 1948) is an American immunologist who holds the position of professor and chair of Immunology and executive director of immunotherapy platform at the M. D. Anderson Cancer Center. His discoveries have led to new cancer treatments for the deadliest cancers. He is also the director of the Cancer Research Institute (CRI) scientific advisory council. He has a longstanding interest in mechanisms of T-cell development and activation, the development of novel strategies for tumor immunotherapy, and is recognized as the first person to isolate the T-cell antigen receptor complex protein.