This paper presents the study design and baseline data from Healthy Directions-Health Centers (HCs), a study designed to address social contextual factors in cancer prevention interventions for working class, multi-ethnic populations. This study is part of the Harvard Cancer Prevention Program Project. Ten community HCs were paired and randomly assigned to intervention or control. Patients who resided in low income, multi-ethnic neighborhoods were identified and approached for participation. This study targeted fruit and vegetable consumption, red meat consumption, multi-vitamin intake, and physical activity. The intervention components consisted of: (1) a brief in-person study endorsement from the participants clinician at a scheduled routine care visit; (2) an initial in-person counseling session with a health advisor; (3) four follow-up telephone counseling sessions; (4) multiple mailings of tailored materials; and (5) linkages to relevant activities in the local community. Fifteen percent of the sample smoked, 86% reported eating fewer than five servings of fruits and vegetables per day, 50% reported eating more than the recommended amounts of red meat, 40% did not meet recommended physical activity levels, and 63% did not take a multi-vitamin on a daily basis. Although overall social support was high, participants reported low levels of social norms for the target prevention behaviors. Other social contextual mediators and modifying factors are reported. By examining the relationships between social contextual factors and health behaviors, it may be possible to enhance the effectiveness of interventions aimed at reducing social inequalities in risk behaviors.