Morphological, physical, and mechanical properties of the blends of poly(vinyl chloride) (PVC) with (ethylene-dimethylaminoethylmethacrylate copolymer) (E-DAM) were studied. From the dynamic mechanical characterization of the PVC/E-DAM blends, it was concluded that E-DAM was slightly compatible with PVC due to the specific interaction between the a-hydrogen of PVC and the tertiary amine group of E-DAM. Measurements of the tensile stress-strain behavior and of the Izod notched impact strength were carried out for a series of PVC/E-DAM blends in the composition range of 0 to 15 wt/o of E-DAM. Improved toughness and impact strength is observed in the case when the amount of E-DAM is 10 wt%. Transmission and scanning electron micrographs of PVC/E-DAM blends show E-DAM domain sizes ranging from 0.1 to 1 mum. E-DAM forms the continuous phase when the composition exceeds 12 wt%. In the ternary blend of PVC/E-DAM/PE, E-DAM acts as a compatibilizer for PVC/PE system. Addition of small amount of PE into PVC/E-DAM blend enhances the toughness of the mixture.