A laser shock processing treatment enables a selectively adjustable and customized compressive residual stress distribution profile to be developed within a workpiece by tailoring the size and shape of the laser beam spots. One peening operation applies to the workpiece a first pattern having relatively large laser beam spots and then applies a second pattern having relatively small laser beam spots. The composite use of such small and large beam spots enables the stress distribution profile to be tailored to the part specifications. The large beam spots maximize the depth of compressive residual stress in the part, while the small beam spots optimize the surface compressive residual stresses of the part. The use of small spot beam patterns allows untreated or improperly processed areas to be laser peened.