The NSF-owned Research Vessel ENDEAVOR, operated under a charter party agreement by the University of Rhode Island, has operated continuously for 16 years. The average projected life of a research vessel is 30 years. This project will make major modifications and upgrades to the vessel to prepare her for the second half of her operational life. The viability of an oceanographic research vessel to conduct the changing needs of ocean science research diminishes with time. The modifications and upgrades will modernize the ENDEAVOR and equip her to be as effective and reliable as when she was originally delivered for service in 1976. The improvements focus on three major areas. Improvements to increase and enhance the ability of the ship to conduct ocean science research; upgrades to improve the day to day operation and maintainability of the ship; and refinements to improve the habitability of the ship. Attention to all these areas will result in a vessel well equipped to continue a long standing tradition of good service to the community of ocean science research.