Long-chain branched (LCB) poly(propylene)s (PP) are synthesized by the incorporation of preformed, vinyl-terminated macromonomers using metallocene catalysts. LCB-PP polymers made with isotactic PP macromonomers are characterized by means of multiangle laser light scattering and extensional viscosimetry. The LCB polymers exhibit enhanced melt properties, such as strain hardening and shear thinning. These properties are critical in many polymer fabrication processes, such as thermoforming, blow molding and foaming.