We investigated the polymerization of methyl acrylate (MA) with three single-site catalysts: a bis(imino)pyridine iron(II) chloride with methylaluminoxane (1), which is compared to bis(4,5,6,7-tetrahydro-1-indenyl)zirconium dimethyl / tris(pentafluorenyl)borane) (2), and a P,O-chelated nickel(II) enolate catalyst (3). Reasonably high polymerization activities were obtained with catalyst (1) exceeding those of catalyst (2) by a magnitude, whereas catalyst (3) results in formation of no polymer. While with catalyst (1) a large maximum of polymerization activity is observed within the first minutes, catalyst (2) results in a rather steady polymerization activity over a longer time. An Fe/Al-ratio and temperature range to obtain high polymerization activities could be identified. The control over the molecular weight properties due to the marked dependence from the Al/Fe-ratio furthermore presents another advantage compared to the alternative of radical polymerization. Ideal molecular weight distributions were obtained with M_w/M_n-values of close to 2 as is typical for single-site catalysts. The polymers are atactic. However, the degree of tacticity is dependent on the polymerization temperature and Al/Fe-ratio. The polymerization follows as expected a coordinative mechanism, and no radical species act as initiators in contrast to polymerizations with some other metalorganic catalysts. Further conclusions about the polymerization mechanism and the active catalyst species will be discussed.