Decentralized systems for drinking water processing could make a significant contribution to the Millennium Development Goals. With the water concept in “self”, Eawag has demonstrated that membrane technology offers the chance to do just that. Lack of drinking water hygiene is one of the main sources of disease transmission worldwide, and in many situations centralized plants cannot be used because of the infrastructure required. Eawag is therefore running several research projects to study sustainable methods of processing water of questionable quality – or even sewage – to produce drinking and service water at the individual household or neighbourhood level. The goal is a simple plant concept suitable for local implementation, with sufficiently low investment costs and preferably low operating and maintenance costs.