The polymerization of methyl methacrylate (MMA) promoted by heterogeneous initiation system (ethyl-2-halopropionate (EPN-X)-CuX-2,2＇-bipyridyl (bpy), where X = Br or Cl) is studied in detail. The results show that ethyl-2-bromopropionate (EPN-Br) is an efficient initiator as expected, and that CuCl-bpy, instead of CuBr-bpy, is a better catalyst for the controlled polymerization of MMA. The solvents with a high value of dielectric constant (epsilon) will lead to fast initiation and narrow molecular weight distribution (MWD). As a result, the controlled, living polymerization of MMA with EPN-Br-CuCl-bpy can be got in ethyl acetate (EAc) at 100 degrees C and in acetonitrile at 80 degrees C. All results suggest that the initiation reaction is a controlling step in the controlled polymerization of MMA. The relationship between the UV spectra of CuCl-bpy and the performances of the polymerization in EAc or acetonitrile suggest that the formation of bis-bpy complex, [Cubpy(2)]X-, will lead to fast initiation and good control of the polymerization,