Photolysis of thin polymeric films of poly-cis[Ru(vbpy)2(py)2]2+ (vbpy is 4-vinyl-4’-methyl-2,2’-bipyridine; py is pyridine) in 0.1 M HClO4 leads to the formation of poly-cis-[Ru(vbpy)2(H2O)2]2+. These films exhibit electrocatalytic behavior toward oxidation of chloride and benzyl alcohol. They can be formed in spatially defined arrays by using contact lithography and selective electropolymerization. The figure illustrates an array of circular polymeric features (375-mum diameter) on a glassy-carbon electrode.