Iron(II) chloride in combination with various polyethers form the homogeneous, "green" catalytic mixtures that are capable of promoting the well-controlled atom transfer radical polymerization of methyl methacrylate in the absence of any additional ligands or solvents. With poly(ethylene glycol)s, linear semilogarithmic plots of conversion vs. time and of molecular weight vs. monomer conversion were obtained with polydispersities as low as 1.32. The effects of the polyether structure, molecular weight, and chain-end functionality on the polymerization kinetics were also investigated.