Information available from recent literature (1—6) is presented in this report on PVC-based, ABS-based, and PC-based polyblends. Property profiles of polyblends are superior to those of component homopolymers. Enhanced properties, combined with the low cost of polyblends, make them economically attractive for special markets (e.g., automotive engineering plastics) and result in better resin utilization. Blend resin attributes which result in a myriad of property improvements in different polyblends are highlighted. A survey of commercially available polyblends has been presented and their commercial utility is indicated. Much polymer science has gone into making polyblends a commercial success. Polyblend technology is a frontier area not only for current research; it will also continue to figure prominently in future developments. Polyblend technology provides attractive opportunities for reuse and recycling of polymer wastes. The discussion covers various compatibility criteria and the use of compatibilization additives in plastic scrap recycling and to enhance the commercial utility of phase-separated blends. Ways of achieving optimum performance in polyblends are discussed. Various criteria for impact modification of PVC have been laid out and the role of rubber morphology in polyblend toughening is pointed out. Polyblending can accomplish a permanent plasticization of PVC and improves its processability as well.