Metal-ligand combination initiators are provided which yield organometallic complexes capable of the polymerization of olefins to high molecular weight polymers. Additionally, these initiators also enable the copolymerization of olefins with functionalized comonomers. These organometallic complexes comprise of a late transition metal with a neutral chelating ligand that contains a Lewis basic functionality in conjugation with an electronically delocalized conduit extending from the metal to the functionality. This structural feature results in a highly active complex, which generates high molecular weight polymers with unique microstructures. Under particular conditions, the organometallic complexes provide for the living polymerization of monomers and comonomers.