The conceptual issues of targeting are well understood. Whether, how and how much to target social services or subsidies to the poor depends on balancing the benefits and costs in a given set of circumstances. The benefit of targeting is that it can concentrate expenditures allocated to poverty alleviation or social programs on those who need them most. This saves money and improves programs efficiency. The costs are the administrative cost of identifying potential beneficiaries, possible economic losses due to disincentive effects and any loss of political support for the programs. It is often assumed that, as the accuracy of targeting and hence the benefits increase, the associated costs will increase as well. Knowledge of the size of the tradeoffs faced in real programs, however, is scarce. Latin American governments have recently become markedly more interested in targeting their social expenditures than they were in past decades. Now that serious attempts are being made to target social expenditures, practical questions are arising about how best to do so. Which targeting mechanisms provide the best targeting outcomes? What are their administrative costs? What are their administrative options and requirements? These, and a host of subsidiary questions, are the focus of this study. It is designed to fill the gaps in our knowledge of the practicalities of administering targeted programs. It should also help to determine whether expectations of targeting success or administrative failure are realistic and what it takes to make targeting work. This book synthesizes information drawn from 23 case studies commissioned for this comparative work and from other sources on seven additional programs. The study focuses on the targeting outcomes and the administrative costs, options and requirements of targeting mechanisms in a variety of social programs in Latin America. This study assumes that all the programs were aimed generally at the poor and that targeting a food supplement program is much the same as targeting the cast transfer program or and education program.