The National Cancer Institute's '5-a-Day for Better Health Campaign is examining the efficacy of interventions in increasing the consumption of fruits and vegetables to five or more servings a day. This paper presents the study design, intervention and baseline survey results of the Treatwell 5-a-Day project, a randomized, controlled worksite-based intervention study. Twenty-two community health centers were randomly assigned to either a Minimal Intervention, Worksite Intervention or Worksite Plus Family Intervention. The Worksite Intervention included participation of employee advisory boards, programs aimed at individual behavior change and programs aimed at changes in the worksite environment. The Worksite Plus Family Intervention incorporated family-focused interventions into the worksite program, including a learn-at-home program, family newsletter, family festival and materials mailings. A self-administered survey was conducted prior to randomization (mean response rate: 87%, n = 1359). Twenty-three percent reported consuming five or more servings of fruits and vegetables a day. Consumption of fruits and vegetables was directly associated with level of household support for healthy eating. The Treatwell 5-a-Day intervention model has the potential to enhance existing worksite-based intervention through incorporation of its family focus, especially given the association of household support with individual eating habits.