Abstract: Bränslesnålare, säkrare och mer komfortabla fartyg samt en effektivare designprocess för nya fartyg.Abstract: The objective is to develop a CFD tool (Computational Fluid Dynamics) for optimization of ships based on computer calculations, as a complement to model testing. Following parameters are used in the optimization: -Water resistance, for low fuel consumption -Manoeuvrability, for safe and convenient operation of the ship -Sea keeping, for safe and comfortable cruising -Propulsion characteristics, for low fuel consumption and vibration free cruising Safer and more comfortable ships with lower fuel consumption and a more efficient design process for new ships.