Many developing countries are witnessing the emergence of a large and growing number of orphans, street children, and children in the worst forms of labor. In particular, conflict and HIV-AIDS have produced a large and growing cohort of orphans in Africa. Low cost solutions are critical if large numbers of orphans and other vulnerable children (OVC) are to be reached, yet there is very little information available on the actual costs of delivering services that assist them. This study estimates the costs of interventions in Benin and Eritrea, in order to determine which sorts of projects are most suitable for scaling up, given limited financial resources. The study measures the average annual economic costs of the project, while the economic analysis of costs used in the study includes depreciation, but also values the opportunity cost of the money tied up in the capital good. A key finding is that institutional solutions are costly compared to family based solutions.