Photoinitiation of acrylate polymerization by [Cr(êta6-arene)(CO)3] complexes in the presence of an organic chloro compound was investigated. For the bimolecular system, a good correlation between activity and metal-arene and metal-carbonyl bond strength was observed. The highest efficiency was found for an initiator in which the organic chloro compound was tethered to the complexed arene: [Cr(êta6-C6H5CH2OCOCCl3)(CO)3]. The initial steps of the photoinitiation were probed and provided evidence for metal-arene bond cleavage in an Cr(êta2-acrylate)(êta6-arene)(CO)2 complex.