This study examined correlates of program initiation and completion in a family-directed program that involved families of adolescents throughout the United States. Correlates varied by whether program initiation, program completion, or the number of activities completed was the indicator of participation. In final regression models, participation was relatively likely by non-Hispanic whites when compared with persons of race/ethnicity other than white, black, and Hispanic; by families with a female adolescent as the program recipient; by families with mothers who had many years of education; and by families with both parents living in the household. There was more participation if parents thought their child would smoke in the future and if the parent thought the adolescent did not smoke currently. Participation was higher if the adolescent felt strongly attached to the parent and if parents did not smoke. The findings are considered in the context of similar programs and future research on family-directed programs to prevent adolescent tobacco and alcohol use.