New three-component photoinitiator systems consisting of a dye, an iron arene complex, and a phenylglycine derivative were investigated through polymerization activity measurements, fluorescence quenching experiments and time-resolved absorption spectroscopy. The efficiency of this three-component (e.g. dye 2/CPG/Complex 1) system in radical polymerization reactions is higher by a factor of three to four than that of two-component systems (e.g. dye 2/CPG). The first step of the photoreaction occurs between the dye and the iron arene complex. An iron arene complex reacts with the singlet excited state or the triplet state of a dye depending upon the nature of the dye used (dye 1 or dye 2). Also, energy transfer occurs in these systems. Finally, the amine derivative reacts with the excited iron arene complex formed after reaction with the excited dye.