An overview is presented of the activities conducted within the NATO STO Task Group AVT-204 to "Assess the Ability to Optimize Hull Forms of Sea Vehicles for the Best Performance in a Sea Environment." The objective is the development of a greater understanding of the potential and limitations of the hydrodynamic optimization tools. These include low and high-fidelity solvers, automatic shape modification methods, and multi-objective optimization algorithms, and are limited here to a deterministic application. The approach includes simulation-based design optimization methods from different research teams. Analysis tools include potential flow and Reynolds-averaged Navier-Stokes equation solvers. Design modification tools include global modification functions, control point based methods, and parametric modelling by hull sections and basic curves. Optimization algorithms include particle swarm optimization, sequential quadratic programming, genetic and evolutionary algorithms. The application is the hull-form and propeller optimization of the DTMB 5415 model for significant conditions, based on actual missions at sea.