Two push-pull dyes (a julolidine derivative DCJTB and a fluorenone-co-amino phenyl derivative h-B3FL), incorporated in multicomponent photoinitiating systems have been investigated for the cationic polymerization of epoxides or the radical polymerization of acrylates under visible light irradiations (household halogen lamp or green laser diode at 532 nm). The DCJTB/iodonium salt (and optionally N-vinylcarbazole) based systems are pretty efficient for the cationic polymerization of epoxides. Both dyes, when combining with an amine and 2,4,6-tris(trichloromethyl)1,3,5-triazine, exhibit a good efficiency in the radical polymerization of acrylates. The photochemical mechanisms are studied by steady state photolysis, fluorescence, cyclic voltammetry, laser flash photolysis, and electron spin resonance spin trapping techniques.