Symmetric laminates exhibit extension-shear or bending-twisting coupling. In a stiffness design of laminates, it is important to make use of coupling terms. The present paper clarifies stiffness characteristics of symmetric laminates using the lamination parameters. The feasible regions of the lamination parameters are examined for several conventional symmetric laminates and stiffness characteristics are represented on the lamination parameter plane. The feasibility and limitation of a stiffness design are discussed for conventional laminates. Based on the fundamental relation of the lamination parameters, a method is developed for determining laminate configurations corresponding to the in-plane or out-of-plane lamination parameters. A genetic algorithm is also applied to the determination of laminate configurations in a stiffness design of laminates.