The institutional arrangements for management of water supply and sanitation in Brazil result from the sector's long history. Initially, British capital was involved, but by the early twentieth century most of the infrastructure was in public hands. Public health engineering was originally closely allied with public health, but gradually municipal engineering diverged from the health sector and the municipalities began building their own water and sewerage systems. Many municipalities have retained control. The figures show significant progress in the past two decades, increasing WSS coverage. However, more than half the rural population still lack improved sanitation facilities, a large proportion of systems require improvements, and the global figures also conceal substantial geographical and socioeconomic disparities. Brazil is seeing a new phenomenon; private capital buys shares in publicly owned water and sewerage companies and forms joint enterprises with them to seek concessions. It blurs the distinction between public and private, and could blur the vision of the inexperienced and under-resourced regulatory bodies. The federal government recently approved a new national plan for water and sanitation. The last one determined the course of the sector for more than 20 years. Time will tell whether this one is as influential.