One of the activities authorized by the Dam Safety and Security Act of 2002 is research to enhance the Nation's ability to assure that adequate dam safety programs and practices are in place throughout the United States. The Act of 2002 states that the Director of the Federal Emergency Management Agency (FEMA), in cooperation with the National Dam Safety Review Board (Review Board), shall carry out a program of technical and archival research to develop and support: improved techniques, historical experience, and equipment for rapid and effective dam construction, rehabilitation, and inspection; devices for continued monitoring of the safety of dams; development and maintenance of information resources systems needed to support managing the safety of dams; and initiatives to guide the formulation of effective policy and advance improvements in dam safety engineering, security, and management. With the funding authorized by the Congress, the goal of the Review Board and the Dam Safety Research Work Group (Work Group) is to encourage research in those areas expected to make significant contributions to improving the safety and security of dams throughout the United States. The Work Group (formerly the Research Subcommittee of the Interagency Committee on Dam Safety) met initially in February 1998. To identify and prioritize research needs, the Subcommittee sponsored a workshop on Research Needs in Dam Safety in Washington D.C. in April 1999. Representatives of state and federal agencies, academia, and private industry attended the workshop. Seventeen broad area topics related to the research needs of the dam safety community were identified. To more fully develop the research needs identified, the Research Subcommittee subsequently sponsored a series of nine workshops. Each workshop addressed a broad research topic (listed below) identified in the initial workshop. Experts attending the workshops included international representatives as well as representatives of state, federal, and private organizations within the United States. Impacts of Plants and Animals on Earthen Dams; Risk Assessment for Dams; Spillway Gates; Seepage through Embankment Dams; Embankment Dam Failure Analysis; Hydrologic Issues for Dams; Dam Spillways; Seismic Issues for Dams; Dam Outlet Works. Based on the research workshops, research topics have been proposed and pursued. Several topics have progressed to products of use to the dam safety community, such as technical manuals and guidelines. For future research, it is the goal of the Work Group to expand dam safety research to other institutions and professionals performing research in this field. The proceedings from the research workshops present a comprehensive and detailed discussion and analysis of the research topics addressed by the experts participating in the workshops. The participants at all of the research workshops are to be commended for their diligent and highly professional efforts on behalf of the National Dam Safety Program. The National Dam Safety Program research needs workshop on Hydrologic Issues for Dams was held on November 14-15, 2001, in Davis, California. The Department of Homeland Security, Federal Emergency Management Agency, would like to acknowledge the contributions of the U.S. Army Corps of Engineers, Hydrologic Engineering Center, which was responsible for the development of the technical program, coordination of the workshop, and development of these workshop proceedings. A complete list of workshop facilitators, presenters, and participants is included in the proceedings.