The electrochemical and photochemical properties of [M(bpy)2bpe Cl]+ (M = Ru, Os; bpy = 2,2′-bipyridyl; bpe = trans-1,2-bis(4-pyridyl)ethylene complexes, both in solution and as spontaneously adsorbed monolayers, were studied. Focus was on the photostability of osmium and ruthenium complexes. Contrary to the osmium systems, [Ru(bpy)2(bpe)Cl]+ were highly photosensitive with either the bpe or chloride ligand being rapidly lost upon visible irradiation depending on the solvent. Monolayers of [Os(bpy)2-(bpe)Cl]+ and [Ru(bpy)2(H2O)Cl2+ were formed and their electrochemical properties determined.