Urban land markets exert a major impact upon the ability of lower income groups to obtain access to adequate shelter and services. When they do not function well, the poor suffer more than anybody else. While the importance of land issues has been widely recognized for many years, urban land tenure and property rights have not been a subject of significant academic or professional interest until relatively recently. This has made it difficult for governments to formulate and implement appropriate policies. This review surveys the extensive international literature on the subject. It proposes a typology which includes statutory, customary and unauthorized tenure systems, as a basis for assessing existing problems and formulating appropriate policies. It concludes with recommendations for improving tenure security which maximize benefits to the poor and minimize market distortion.