The introduction of composite materials and the ability to tailor these materials to improve aerodynamic and structural performance is having a distinct effect upon aircraft design. In order to optimize the efficiency of the design procedure, a design process which is more integrated than the traditional approach is required. Currently the utilization of such design procedures produces enormous computational costs. An ongoing effort to reduce these costs is the development of efficient methods for cross-disciplinary sensitivities and approximate optimization techniques. The present research concentrates on investigating the integrated design optimization of a subsonic, forward-swept transport wing. A modular sensitivity approach for calculating the cross-sensitivity derivatives is employed. These derivatives are then used to guide the optimization process. The optimization process employed is an approximate technique due to the complexity of the analysis procedures. These optimization results are presented and the impact of the modular technique is discussed. / Master of Science