Electrochemical oxidation of organics at thermally prepared DSA type metal oxide anodes has been studied. In reactions involving only simple electron transfer, oxide electrodes exhibit an electrocatalytic activity similar to that of noble metal electrodes. In oxidation reactions of more complex mechanism, oxide anodes show no electrocatalytic activity below the potential of oxygen evolution and oxidation of organics can take place only under conditions of simultaneous oxygen evolution. A simplified mechanism of organics oxidation catalyzed by intermediates of oxygen evolution has been proposed distinguishing between two limiting electrode behaviors: (i) At `non-active` anodes (typically fully oxidized metal oxides) oxidation of organics occurs at a high potential and leads to their combustion through physisorbed hydroxyl radicals, (ii) At `active` electrodes (IrO₂, RuO₂) the reaction takes place at lower potentials characteristic of the metal oxide and results in a selective oxidation of the organic compound at higher oxidized metal oxide surface sites. A kinetic model of organics oxidation competed by oxygen evolution at `active` type anodes is also proposed and confirmed by preparative electrolysis.