According to the Joint Monitoring Programme for Water Supply and Sanitation (WHO/UNICEF), 89% of the world population has access to an improved source of drinking water. However, this percentage needs to be put into perspective as it does not take into account the quality of the water, the geographical distribution of the water supply points and the dependability of the support services. Inadequate access to water may have many causes: social, technical, financial, managerial, institutional or environmental. To provide all layers of the population with access to sustainable drinking water supplies, Protos has adopted a holistic approach. The use of appropriate technologies, locally directed projects, pricing policies adjusted to social contexts, local participatory management structures supported by local authorities and protection of the water source environment: all these are elements that need to be addressed to achieve proper access to water.