Abstract In recent years, decentralization has been upheld by governments, donors and policy makers in many developing countries as a means of improving public services although opinion is divided on the link between decentralization and service delivery. This article reviews recent literature and research on decentralized service delivery in Tanzania. It uses the principal-agent theory and broader decentralization frameworks to describe and compare decentralization in two sectors: water and health. The analysis shows that decentralization between the two sectors differs, with the water sector displaying a mixture of bottom-up and top-down models while the health sector is more centralized with an orientation towards the top-down model. It is concluded that decentralized service delivery in Tanzania takes on different forms where the nature of sector is an important factor in the kind of institutional arrangements, in which gender plays a role as we…