In many African countries, in some cases public services can be contracted to private sector entities by delegation under agreed conditions. Such delegation occurs, at the local authority level, in diverse fields such as waste management, public transport or water distribution. Whereas the principal agent theory explains that the delegation of a public service can be exposes to information asymmetry, it is important to question about the social performance of this institutional arrangement. In the specific case of the public service of solid waste management, the research of a fulfilling institutional arrangement must include three orders of constraints that go from the economic, institutional and political context related to the solid waste management to the informational, transactional and administrative constraints proper to all agency relation. This paper proposes to build a composite performance indicator of the public service of solid waste management. This indicator is constituted of a set of values that are necessary in all process of a public service assessment of solid waste management. It takes in account the institutional aspects bound to the solid waste management and based on sustainable development concept. Four modules constitute our composite indicator of performance: the institutional, social, economic and environmental module. This one fills a function of basis of information for the political decision making, but also a function of assessment or audit, intern and/or external of a public service of solid waste management in the African context in general and of the Cameroonian in particular. However, it is incumbent upon the African States to find the socially desirable compromise between these different values