Family based services attempt to maintain and strengthen the client family and prevent family dissolution and the placement of a child or several children in substitute care. This study compared programs that serve children and their families in their home. Variances in program costs were attributed to differences in number of casework hours per family, staffing patterns, salary differentials, accounting, and collection methods. All programs reported significant results in preventing substitute care placements for the children of families served. While family based prevention services are more labor intensive, substitute care costs are more substantial. In a second study, a state social service division was prospectively analyzed to project expenditures and cost savings for family based services and substitute care. Family based services were expected to prevent placement of 60 percent of the children with a net cost savings for the social services department. (ABL)