The Law nº 11.445/2007 establishes guidelines for basic sanitation in Brazil, pointing the planning as a fundamental aspect of services management, among other enforcements. Aiming at contributing to this discussion, this article intends to identify the main factors that challenge the planning process at the municipal level, especially in small size municipalities, and the aspects that motivate the development of the plan. The study uses qualitative methodology to collect and analyze the data, conducting semi-structured interviews with managers of 15 municipalities located in the Zona da Mata of Minas Gerais, and applies the technique of the Collective Subject Discourse as analytical tool. The main difficulties identified are unavailability of financial resources and limitation regarding professional qualifications and municipal expertise. However, after overcoming the first obstacle, the qualification problem can be partially solved by training and contracting professionals, which can also lead to overcoming the methodological difficulties. Issues such as sector integration of areas that encompass the basic sanitation structure, political will and other factors were also identified as barriers to planning. Despite the difficulties, planning is seen with optimism and significant motivation, and one can realize that the fulfilment of the law could not be the main driver for the managers, but strongly their conviction of the real benefits
water and sanitation; planning; water and sanitation municipal planning