The Symposium on Cooling Water Intake Technologies to Protect Aquatic Organisms brought together professionals from federal, state, and tribal regulatory agencies; industry; environmental organizations; engineering consulting firms; science and research organizations; academia; and other organizations concerned with mitigating harm to the aquatic environment by cooling water intake structures. The efficacy and costs of various technologies to mitigate impacts on aquatic organisms from cooling water intake structures, as well as research and other future needs, were discussed. The Symposium was cosponsored by USEPAs Office of Water and Office of Research and Development, National Oceanic and Atmospheric Administration, U.S. Department of Energy, and Electric Power Research Institute and in cooperation with Riverkeeper, Inc., Utility Water Act Group and Atlantic States Marine Fisheries Commission and was held May 6-7, 2003 in Arlington, Virginia. This document presents the proceedings of the Symposium. It includes, where available, technical papers, copies of the slides used by presenters, a transcription of questions and answers raised during the symposium, as well as other information presented at the symposium.