Assessment of welfare gains from a targeted social program can be seriously biased unless the endogeneity of program participation is addressed. Bias comes from two sources of placement endogeneity: the purposive targeting of geographic areas, and the targeting of individual recipients within selected areas. Partial decentralization of program…

Twenty-five years of evaluation research are reviewed. Findings show that evaluations of social programs have been negative. Policymakers often blamed the evaluators when it was not clear why certain programs had failed. There is hope for a better working relationship as evaluators adopt better methods and social policy becomes more rational. (VM)