The copolymerization of dimethyl itaconate and methyl methacrylate with 2,2’-azobisisobutyronitrile was investigated kinetically at 50 degrees C in benzene. The copolymer composition conforms to the terminal model within experimental error, but the variation of the copolymerization rate shows a penultimate effect on the propagation reaction. Homopolymerization kinetic coefficients for dimethyl itaconate monomer were also determined.