The Gulf-wide Information System (GWIS) is a cooperative project between the Minerals Management Service and Louisiana State University to develop a geographic database to support oil spill contingency planning in the U.S. Gulf of Mexico. The objectives of the project are to develop a regionally complete and consistent database from Florida to Texas that can be used for oil spill planning as well as for other environmental and planning applications. The GWIS project includes a Steering Committee to develop consensus on database structure and contents. The Steering Committee includes representatives from state and federal agencies and the oil industry. The GWIS database will be completed during the next two years. A prototype of GWIS has been developed for coastal Mississippi that shows the data layers and how they will be queried and used for oil spill planning.