Abstract: A method for the anionic photoinitiation of polymerization or crosslinking of a substrate by irradiating a mixture of a substrate and a photoinitiator, where the photoinitiator is an inorganic transition metal complex which releases on irradiation a polymerization initiating substance consisting essentially of an anionically charged nucleophile that initiates the polymerization or crosslinking reaction, under conditions that allow the anion to initiate polymerization. FIG. 3 is plot of percentage polymerization of ethyl .alpha.-cyanoacrylate containing different concentration of Reineckate's anion.