Process evaluations are critical in determining whether outcome evaluations are warranted. This study assessed the extent to which a childhood obesity prevention initiative, "NY Fit WIC", was adopted and implemented by the New York State Supplemental Nutrition Program for Women, Infants and Children (WIC). Process data came from qualitative telephone interviews of 101 WIC local agency directors, following "NY Fit WIC" trainings. Activities were summarized and cross-tabulated by target level (i.e. participant, staff, agency or community) and by theoretical construct (i.e. knowledge promotion, skill building, self-efficacy or role modeling). Approximately 528 activities were reported across all WIC agencies. When activities were grouped into similar categories, 123 unique activities were identified. Agencies were more likely to implement physical activity-related activities (67%) than nutrition-related activities (33%). The majority of activities targeted WIC participants (47%) and staff (22%) and focused on skill building/self-efficacy (67%) among participants and on role modeling (61%) among staff. The involvement of all agencies shows a high level of adoption of the initiative. The diverse number of activities suggests that WIC local agencies tailored implementation to match their resources and clients' needs as planned. These results suggest that an outcome evaluation is warranted to determine whether meaningful behavioral changes occurred among WIC participants and staff.