Technical Abstract: Researchers at the National Sedimentation Laboratory have made important contributions to reservoir sedimentation research for most of the 50 years that the laboratory has existed. Early publications from the mid 1960s to the mid 1970s reported work on the development of gamma ray sediment measurement instrumentation, surveys of lakes, and the use of Cs-137 for sediment dating. During the late 1970s, the focus of the work was on the use of reservoir sedimentation data to identify relationships between drainage areas and erosion, sediment trapping efficiency, and continued work with radionuclides. During the 1980s, ecological aspects of reservoir sedimentation were studied, with a main focus on contamination of stored sediments being an important topic for research. Sedimentation work in 1990s shifted toward examining sediment impairment in aging man-made structures in a variety of scales. Recent work has focused on the reconstruction of watershed erosion history by using a combination of physical, chemical and radiochemical techniques to glean information from ancient sediment deposits in natural lakes. In partnership with the National Center for Physical Acoustics, ongoing research is seeking to improve the use of acoustic techniques for quantifying the volume of sediment deposits in lakes. The current paper will consist of a brief summary of the contributions made by scientists at the National Sedimentation Laboratory to reservoir sedimentation research.