In the world today, there are roughly 25 million cancer survivors. Although the increasing numbers of survivors testifies to the success of early detection and treatment, there is a downside. Cancer survivors are at increased risk for second cancers, other forms of comorbidity (e.g., cardiovascular disease, diabetes, osteoporosis), and functional decline. Lifestyle factors, such as a healthy diet, regular exercise, and smoking cessation may prevent these conditions and improve survivors' quality of life. Data also are accumulating to suggest that healthful lifestyle practices and successful weight management may prevent progressive or recurrent disease. Previous surveys conducted among both adult and pediatric cancer survivors indicate that most survivors have high levels of interest in diet and exercise interventions. Additionally, survivors who smoke report high levels of interest in interventions aimed at smoking cessation. Many factors, such as intervention timing and duration and channels of delivery, must be carefully considered in developing interventions that best meet the needs of this vulnerable population. Total transparency also is necessary in reporting the results of trials to ensure the inclusion of information regarding proportional accrual, attrition, and study sample sociodemographic characteristics to move toward the development of interventions most likely to gain broad-scale acceptance and adherence. Home-based interventions that rely on telephone counseling, mailed materials, or computer-assisted approaches offer promising means of reaching the geographically dispersed population of cancer survivors. More research is necessary to develop interventions that can reach and effectively promote long-term behavior change in this ever-increasing population. © 2007 American Society for Nutrition.