© 2015 American Cancer Society. Answer questions and earn CME/CNE The importance of expanding cancer treatment to include the promotion of overall long-term health is emphasized in the Institute of Medicine report on delivering quality oncology care. Weight management, physical activity, and a healthy diet are key components of tertiary prevention but may be areas in which the oncologist and/or the oncology care team may be less familiar. This article reviews current diet and physical activity guidelines, the evidence supporting those recommendations, and provides an overview of practical interventions that have resulted in favorable improvements in lifestyle behavior change in cancer survivors. It also describes current lifestyle practices among cancer survivors and the role of the oncologist in helping cancer patients and survivors embark upon changes in lifestyle behaviors, and it calls for the development of partnerships between oncology providers, primary care providers, and experts in nutrition, exercise science, and behavior change to help positively orient cancer patients toward longer and healthier lives.