This Advisory report responds to a request from EPA's Office of Water (OW) for EPA's Science Advisory Board (SAB) to provide advice on technologies and systems to minimize the impacts of invasive species in vessel ballast water discharge. Vessel ballast water discharges are a major source of non-indigenous species introductions to marine, estuarine, and freshwater ecosystems of the United States. This assessment was conducted by the SAB s Ecological Processes and Effects Committee (EPEC) as augmented with additional Panel members having expertise in ballast water issues and water treatment (collectively referred to as the Panel).