Eating and physical activity behaviors that confer risk for chronic disease are prominent among women from varying ethnic and racial groups who are low income. Conceptualization and development of a theory-based behavioral intervention to address their unique needs during the first year following childbirth comprised four steps: (a) translating public health guidelines and emerging epidemiologic data into specific intervention messages; (b) developing practical strategies to operationalize theoretical constructs, in the context of a social ecological framework; (c) stating achievement-based objectives and writing scripts for five home visits; and (d) conducting formative research. Focus group participants expressed a desire for a "health mentor," not somebody who "nags" or "stresses you out." Paraprofessionals from the Expanded Food and Nutrition Education Program (EFNEP) were directly involved in pretesting the intervention and remain involved as health mentors. This intervention can serve as a basis for future organizational partnerships to benefit the health of populations who are low income.