The photolysis of copolymers of anthrylmethyl vinyl ketone (AMVK) with styrene and methyl methacrylate has been studied, both in solution and in the solid phase. Quantum yields of the order of 0.01 were observed in both cases for release of the major product, methyl anthracene (MA). Photolysis of an aqueous emulsion of a styrene-AMVK copolymer showed similar yields of MA. The results indicate the possibility of using the Norrish type I process as a means of releasing drugs or other biologically active compounds from polymeric matrices.