The Safe Drinking Water Act and its Amendments (SDWAA) have given EPA an aggressive standard setting agenda. The agenda, if carried out fully, will impact on water utilities in the U.S. EPA's Drinking Water Research Division (DWRD) is responsible for evaluating technologies for meeting the MCLs to be established under SDWAA. The purpose of the paper is to discuss DWRD's current research intended to support the MCL development process. Work is actively being conducted in the following areas: identification and control of disinfection by-products; use of microcolumn and adsorption modeling to predict usage rates for granular activated carbon (GAC); cost of GAC systems; use of ozone and ozone/H2O2 for oxidation of organics; reverse osmosis; radon removal; calculation of C.t values; and control of water quality in distribution systems. Among the most promising technologies for organic removal are ozone, ozone in combination with other oxidants, and reverse osmosis (ultrafiltration). Work will also continue in examining various techniques for disinfection of pathogenic organisms.