The purpose of this paper is to clarify the mechanism of water and sanitation management in the Abese indigenous quarter of La district, Accra, Ghana. This informal quarter is mainly composed of community relatives known locally as clan, who are the core actors in the management of common facilities, including water and sanitation. The north area of the Abese quarter is a traditional residential area. On the other hand, south area was originally farmland and gradually expanded as a residential area due to population growth. It's clear from the study that all 15 clan houses are in located in the north area. The field survey revealed a clear mechanism of consensus oriented clan management which was achieved through three weekly meetings and joint investments in water and sanitation. In relation to water and sanitation : sewers, bathrooms, toilets, water tanks, tap, the treatment and supply methods of water and sewage are grasped. Then, through the field survey, the distribution of each facility were identified and indicated on the Map. In addition to that, through interviews, we clarified the actual condition of construction and maintenance, focusing on original proposer, funding source, workers (clan labor or company), ownership and use, and management in sharing. Furthermore, the construction and maintenance of water and sanitation was classified and modelled based on the internal (inside Abese) and external (outside Abese, including government) actors involved in management. As a result, 4 types and 6 patterns were identified. The 4 types include: (A) Clan type, (B) Private-Collective type, (C) Private-Individual type, and (D) Public works type. Basically, it is noteworthy that although management of Abese has been utilizing support from outside the district and the government when needed, the community emphasizes clan and residents inspired "maintenance and management in the quarter ". These are made possible, as identified through the survey, by factors such as the existence and influence of clans, the existence of key persons, way of joint maintenance, and the mechanism of shared use.