The liquid phase photolysis of some 35 liquid alkyl disulfide mixtures has been studied. The corresponding unsymmetrical disulfide is the only significant product of the reaction and the System attains a photo-equilibrium state at longer exposure times. Product formation is completely eliminated by the addition of nitric oxide.Quantum yields have been redetermined for the methyl disulfide – ethyl disulfide System using four different light sources. Initial rates have been measured for each of the 35 combinations and have been shown to be a function of total molecular weight of the disulfide mixture and to be strongly influenced by steric factors. These effects are most pronounced for mixtures wherein the exchange reaction between thiyl radical and a symmetrical disulfide is important as indicated by quantum yields above unity. Combinations of isodisulfides give rise to anomalously high rates.