The enzymatic degradation of blends of poly(β-hydroxybutyrate-co-16% β-hydroxyvalerate) with polystyrene, and styrene-acrylonitrile copolymers was studied. Degradation has been measured by weight loss after exposures to the extracellular depolymerase from Penicillium funiculosum. Degradation rates of solution cast blends have been compared with injection molded strips. Blends prepared by injection molding showed a maximum in degradation rate for the 50 50 blends. Blends prepared by solution casting exhibited higher rates for the higher P(HB-co-16% HV) content samples and faster degradation rates compared to those for injection molding.