In the past, a wealth of data has been collected from the Galveston Bay system, relating to the movement and quality of water, the biology of the bay, navigation, socioeconomics and fisheries, some of this information dating back more than a century. Therefore one of the early tasks in the National Estuary Program (GBNEP) was to locate and inventory these data. The specific objectives of this project were to: (1) survey local, state, and federal agencies and other organizations for data sets; (2) prepare in a standard format written descriptions of data sets; and (3) compile the data inventory in an electronic, searchable, microcomputer-based information base. The product of the project should enable a researcher with a specific data requirement to determine where (and whether) the historical data exist and how to access them.