Radiation therapy and immunotherapy in partnership may have the capability of delivering a therapeutic effect exceeding the sum of its parts. The possible relationship has been demonstrated in murine models and has been extended to a variety of clinical trials. Though the standard notion of whole body radiation therapy is immunosuppressive, there is growing evidence toward the contrary for focal radiation therapy. Furthermore, if immunotherapeutic techniques can retune the immune system against cancerous cells, they should have obvious benefits for advanced treatments moving forward. Herein, we explore the promise in combining radiation therapy and immunotherapy with distinct focus on potential morbidities and toxicities through analysis of completed clinical trials.