Experimental results on the photochemical transformations and structure of some Fe(III), Fe(IV), Ru(IV), Mo(IV) dithiocarbamate complexes have been considered. Attention is paid to the photochemistry of the Ni(IV) dithiocarbamate complexes. The solutions of these complexes show high photochemical activity even in the red spectral range, which is very unusual for photochemical systems. Moreover, these solutions are photochromic systems. Using laser flash photolysis, it has been shown that some phototransformation steps occur inside the coordination sphere of the nickel ion. The reverse dark reactions are bimolecular processes.