AbstractLaser flash photolysis was used to investigate the formation of radical ions produced in the quenching of the pyrene‐N,N'‐dimethylaniline exciplex by reverse micelles made with benzylhexadecyldimethylammonium chloride (BHDC) dispersed in benzene or chlorobenzene. The radical ion quantum yields, φion, were determined as a function of BHDC concentration and the amount of water dispersed. They were strongly dependent on the composition of the media. The charge separation was more effective in the BHDC‐benzene than in the BHDC‐chlorobenzene system. The results are discussed in terms of the properties of the micellar interface and the fast exchange of material produced by collisions between reverse micelles.