This article discusses the U.S. Environmental Protection Agency's (USEPA's) new drinking water strategy, focusing on the first of four elements proposed in the strategy -- address contaminants as groups, rather than one at a time, in the hope that enhanced protection of public health can be achieved more cost-effectively. In particular, the article focuses on three of the groups -- nitrosamines, carcinogenic volatileorganic chemicals (VOCs), andchlorinated disinfection byproducts (DBPs) -- that USEPA believesit has enough information onfor a decision regarding regulatory action.Includes 11 references,.