Parametric modeling is an incredibly powerful tool during the design process. This technique allows a wide range of options in the design space to be quickly created and evaluated, resulting in a fast convergence towards the optimal design point. At DEKC Maritime, parametric modeling is used extensively for hydrodynamic and structural analysis. With parametric 3D CAD software, the hull and appendages of any vessel can be set up in a smart and stable manner, using a minimum number of design variables to achieve maximum variation in the form. This is then automatically linked to our CFD software, and advanced optimization algorithms subsequently guide the design to its optimum. Parametric modeling has been used in this way both for optimizing new appendages on existing hull forms, as well as creating completely new hull forms built up parametrically from scratch.