Organonickel complexes [(R'terpy)Ni(aryl)]X (R'terpy=derivatives of 2,2',61,2 ''-terpyridine; aryl=2,6-dimethylphenyl=Xyl or 2,4,6-trimethylphenyl=Mes; X=Br or PF6) have been investigated by multiple electrochemical methods as well as combined electrochemical/spectroscopic techniques (spectroelectrochemistry). Reversible electrochemical reduction fills successively pi(*) orbitals in the terpy ligand. Some of the occurring species were characterized spectroscopically (EPR and UV/vis/NlR spectroelectrochemistry). The presumably nickel-centered oxidation occurs irreversibly.