The cage effects of radical pairs produced by photolysis of p-methyl dibenzyl ketone, 1, as well as the fluorescence spectra of pyrene, 2, and 1,3-di-a-naphthylpropane, 3, in aqueous solutions containing TX100 (TX) have been determined as a function of the concentration of TX and of the concentration of added ionic surfactants [sodium dodecylbenzene sulfate (SDBS) and cetyl trimethylammonium bromide (CTAB)] and neutral electrolytes. The results indicate that both the aggregation and micellar properties of TX are significantly influenced by the molecules of 1 solubilized in TX micelles. The results also show that comicelles are formed between TX and ionic surfactants and that the interior polarity of TX micelle is lowered by the addition of ionic surfactants. Neutral electrolytes are found to have at least two effects upon the aggregation of TX and ita micellar properties: increasing ionic strength increases the dissimilarity between the TX micelle and the water phase and thus decreases the critical micelle concentration (cmc) and simultaneously enhances the interior micellar microviscosity. In addition, at a high concentration of electrolytes, the micellar volume changes. It is suggested that only the ions bonded onto the surface of the micelles significantly influence micellar parameters such as microviscosity and cage effects.