Welcome to The U.S. Environmental Protection Agency (EPA) Workshop on Innovative Approaches for Detecting Microorganisms in Water. The missionof the EPA is to protect public health and to safeguard and improve the nations natural environment, air, water, land upon which life depends. Success at EPA is dependent, in large part, on our ability to make credible environmental decisions based on solid scientific information and technical methodologies. This workshop, co-sponsored by EPAs Office of Research and Development and the Rapid Detection of Microbial Contaminants of Water Work Group in EPAs Environmental Technology Center(ETC; http://www.epa.gov/ etop/etc/index.html), is intended to facilitateprogress on the quantitative assessment of microbial agents in water. Reliable, sensitive, robust, and versatile detection and monitoring tools are needed to address the risk assessment and management of known and emerging microbial contaminants in source water, treated water, and/or in distribution systems.