The results of investment in irrigation projects in developing countries have often been disappointing both to investors and to local beneficiaries. The editors argue that the ultimate goals of irrigation projects must be set within the larger context of general social issues. Economic efficiency must often be weighed against social gains; irrigation projects cannot be conceived simply as technical problems, and structures must be designed with reference to their continuing maintenance and operation. Using a management model, the contributors offer new perspectives on the evaluation of investment priorities and the potential benefits of irrigation projects in developing countries. Recommendations on evaluating investments in small-scale irrigation projects, improvements in water allocation, project rehabilitation and maintenance, water pricing, government food policy, technical assistance, and project sustainability are empirically grounded in studies from India, Thailand, Pakistan, and Egypt. The analysis of specific small-scale projects suggests that there are many opportunities for improving farmer participation and thus increasing the chances of success for these projects.