An increasing number of developing countries are introducing School-Based Management (SBM) reforms aimed at empowering principals and teachers or at strengthening their professional motivation, thereby enhancing their sense of ownership of the school. Many of these reforms have also strengthened parental involvement in the schools, sometimes by means of school councils. SBM programs take many different forms in terms of who has the power to make decisions as well as the degree of decision-making devolved to the school level. While some programs transfer authority only to school principals or teachers, others encourage or mandate parental and community participation, often in school committees. SBM has the potential to be a low cost way of making public spending on education more efficient by increasing the accountability of the agents involved and by empowering the clients to improve learning outcomes. By putting power in the hands of the end users of the service, SBM eventually produces better school management that is more cognizant of and responsive to the needs of the end users. This study reviews more than 20 country experiences with SBM in Latin America and the Caribbean, Africa, Asia, and the Middle East and North Africa, as well as more developed countries such as the United States, the United Kingdom, the Netherlands, Australia, and New Zealand. For each of these countries, a brief description of the SBM reform along with any evidence regarding its impact on a variety of indicators, from student test scores and dropout and repetition rates to parent and teacher perceptions of the reform's benefits, is included. The general finding is that SBM has had a positive impact on some variables - mainly in reducing repetition and failure rates, and in improving attendance rates - in contrast to its mixed results on variables such as test scores which could be due to timing. It is a reasonable assumption that SBM needs about five years to bring about fundamental changes at the school level and about eight years for changes in difficult to modify indicators such as test scores to become evident.