As cancer immunotherapies have emerged as front-line therapies, it has become clear that advancing computational approaches to cancer immunology is critical to better understanding the role of the immune system in cancer. Despite the enormous promise of immunotherapy, success is still limited to a minority of patients and tumor types. Through a better quantitative understanding of how immunotherapies work and how the immune system reacts to them, the Program in Computational Immuno-Oncology hopes to play a role in extending the benefit of immunotherapies to a larger set of patients, and in gaining new insights on malignant-immune cell interactions. Several next-generation computational approaches to understanding tumor evolution are being advanced in the Computational Oncology Service. At the same time, there have been significant advances in high-resolution quantitative immunology and the immune driven evolution of pathogens which should be brought into cancer research areas such as response to immunotherapy and the role of immune system in the tumor microenvironment.  Our Program aims to bring such approaches to bear on problems in cancer immunology and immunotherapy by bridging the Computational Oncology Service and the Parker Institute for Cancer Immunotherapy.