Parametric optimization was applied to a double-hull AFRAMAX tanker design in order to reduce oil-outflow probability and increase cargo carrying capacity, and the results are presented here. A multi-criteria optimization procedure was set up in modeFrontier® using the cargo volume, the mean oil-outflow parameter and the steel weight of the cargo block as the objective functions. Calculations are based on a parametric geometric model of the ship created in NAPA®, and on a structural model created in POSEIDON®. Integration of the above software packages leads to an automated optimization procedure that provides improved feedback to the designer regarding the trade-off between the various design parameters and optimization criteria involved. The results obtained suggest notable improvements in transport capacity and oil-outflow performance for known, well-established yard designs. The presented work derives from a joint industrial project between Germanischer Lloyd (GL) and the Ship Design Laboratory of the National Technical University of Athens (NTUA-SDL), which continues the work done and coordinated by NTUA-SDL within the SAFEDOR project on the same subject.