One of humanities biggest problems at present are millions of preventable deaths in developing countries. Most of those deaths are caused by microoganisms, often from sewage contaminated drinking water. Hence, technology to remove such contaminants is a first step to solving the problem. One such technology is ultrafiltration (UF). UF is a membrane filtration process in which water is pushed through a physical filter with a transmembrane pressure supplied by a pump or gravity. The pore size of such membranes is such that bacteria and most viruses can be effectively retained. As a consequence, this process has the ability to disinfect water physically and hence prevent water related disease and death from microorganisms. In this paper the performance of existing UF membranes and systems will be reviewed in terms of pathogen removal, water productivity (system capacity and flux), specific energy consumption per volume of water produced, which affect cost. Specific needs of systems to be installed and operated in developing countries as well as opportunities for the global community will be outlined.