Vehicle manufacturers are faced with challenges arising from EU regulations which concern the eco-friendliness of their future cars. A light-weight body structure can contribute to low operational cost and fuel consumption. In this paper the optimization of a carbon fiber reinforced plastic body for a future city car is described. The objective was minimal weight, while fulfilling constraints regarding stiffness and load bearing capabilities, and considering the manufacturability in the modeling and optimization process. The frame consists of numerous parts with laminate lay-ups of different complexity. Practical approaches needed for the parameterization of the lay-ups as well as their post-processing and their implementation with ESAComp and ANSYS Composite PrepPost are illustrated. This paper demonstrates how the simulation tools were efficiently applied in the process integration and design optimization environment modeFrontier to find the best feasible design for the challenge.