Abstract : MariSTEP is a DARPA/MARITECH sponsored cooperative agreement among several shipyards, CAD vendors, and a major university to prototype the exchange of shipbuilding data between diverse shipyard environments using STEP, an International Standard for the Exchange of Product Model Data. The goal of the three year MariSTEP effort is to implement transfers using the STEP Shipbuilding Application Protocols to exchange product model data among the participating shipyards. The project is in its first year, and this paper reports on the progress made thus far, along with outlining the overall project plans.