The behavior of Ti‐supported Pt‐Ir alloys in the electrolysis of has been examined as a function of Ir content, concentration, and electrolysis time. Short‐time experiments show that an iridium content as low as 0.5% is sufficient to eliminate almost completely the passivation effects (in 1M and saturated solution). Long‐run experiments make clear that the minimum percentage of 5/10% Ir is necessary in order to have low potentials after thousands of hours; in such a case, however, complicating factors such as mechanical stability and chemical corrosion should be taken into account.