This paper investigates the integration of Building Performance Simulation (BPS) and optimization tools to provide high performance solutions. An office room in Cairo, Egypt was chosen as a base testing case, where a Genetic Algorithm (GA) was used for optimizing the annual daylighting performance of two parametrically modeled daylighting systems. In the first case, a combination of a redirecting system (light shelf) and shading system (solar screen) was studied. While in the second, a free-form “gills surface” was also optimized to provide acceptable daylighting performance. Results highlight the promising future of using computational techniques along with simulation tools, and provide a methodology for integrating optimization and performance simulation techniques at early design stages.