Composite panel structure optimization is commonly decomposed into panel optimization subproblems, with specified local loads, resulting in manufacturing incompatibilities between adjacent panel designs. A new method proposed here for constructing globally blended panel designs uses a parallel decomposition antithetical to that of earlier work. Rather than performing concurrent panel genetic optimizations, a single genetic optimization is conducted for the entire structure with the parallelism solely within the fitness evaluations. A genetic algorithm approach, based on locally reducing a thick (guide) laminate, is introduced to exclusively generate and evaluate valid globally blended designs, utilizing a simple master–slave parallel implementation, implicitly reducing the size of the problem design space and increasing the quality of discovered local optima.