Immunotherapy has had a profound impact on how we treat cancer. Immunotherapy takes advantage of the body’s immune system to combat the disease and is considered as one of the pillars of cancer care together with chemotherapy, radiation therapy, and surgery. This introductory chapter provides a brief overview of the different types of cancer immunotherapies currently available, their mechanisms of action, and the benefits and potential side effects. Despite the success of these emerging therapies, resistance remains a genuine concern. Thus, mechanisms of resistance to immunotherapy are also briefly discussed. In addition, an overview of the various combination therapies such as chemotherapy, radiation therapy, and targeted therapy, that are currently used in combination with cancer immunotherapy, is presented. Finally, the chapter highlights how a “Team Medicine” approach could enable all eligible cancer patients to receive this promising treatment to treat their respective cancer types. More, detailed information regarding the different immunotherapies as well as their combinations when applicable in different cancers is discussed in the ensuing chapters dedicated to individual cancer type.