Survival rates for certain types of cancer have improved over the past few decades. Changing unhealthy behaviors such as smoking, poor diet, and sedentary life-style among individuals who have been diagnosed with cancer may help to reduce cancer treatment sequelae, possibly reduce risk of recurrence for specific types of cancer, and reduce risk for other common diseases such as cardiovascular disease, obesity, and hypertension. This article reports the prevalence of each of these behaviors among those diagnosed with cancer and reviews interventions that have targeted these risk behaviors. There is considerable variation in the type of research questions asked, the methodologic quality of the research, sample sizes, and the outcomes observed across studies focusing on changing the three health risk behaviors. In the final section, we provide guidelines for researchers in developing health behavior interventions for individuals diagnosed with cancer and highlight challenges that should be addressed.