Though many studies have examined the level of physician obesity prevention counseling among the general population, little is known about how homeless patients are advised about healthy eating and physical activity by their health care provider. The homeless are an at-risk population with whom physicians and other health professionals can play a vital role in helping them to be healthy by means of Health Education and involvement in policy development and advocacy. The purpose of this feature article is to review previous work conducted with the homeless that assesses their risk for obesity and other chronic diseases due to limited access to health care, as well as system-level barriers that lead to poor dietary and physical activity behaviors. The article then discusses the need for physician counseling among this population while integrating a socioecological framework and working across multiple systems when counseling homeless populations on nutrition and physical activity topics.