Progress in rural access to sanitation is far behind agreed targets, especially in Sub-Saharan Africa. As a result, new policies are being defined, which shift the role of public investment from infrastructure to sanitation promotion, and give the responsibility of service delivery to local government. This paper analyzes the role that local governments can have in sanitation promotion in this new framework. The implementation of the National Sanitation Campaign in Tanzania is analyzed using the Problem Driven Governance and Political Economy methodology. Results show that direct implementation enhances local governments´ commitment, but that not all functions carried out are suited to their capacities, motivations and constraints. The challenges identified emerge as a combination of technical weaknesses in the implementation of the adopted methodologies, the political economy of local governments, and the economic and social particularities of rural areas, which are similar to other countries across the region. Recommendations for a more effective service delivery model are made, balancing the role of local government between direct execution, coordination and supportive supervision. The fact of having a government programme with some direct implementation can bring about important differences in the national ownership of, and interest in rural sanitation, which are greatly needed.