This paper describes the kinetics of the ceric ion-initiated graft co-polymerization of vinyl acetate-acrylonitrile to poly(vinyl alcohol). The graft copolymerization rate Rpwas found to be first order with respect to the total concentration of the comonomer mixture [M], the concentration of vinyl alcohol repeating units [PVA], and the mole fraction of vinyl acetate in the comonomer feed mixture. Rpwas independent of cerous ion. The grafting rate was independent of ceric ion above a ceric concentration of 0.0020 M but first order in ceric ion below that concentration. Rp initially increased rapidly with [H+] to a maximum and then decreased and levelled off at hgher [H+]. The rate of ceric ion disappearance was first order in [PVA], independent of [MI, and increased with increasing [H+] with a leveling off at high [H+]. A reaction mechanism.