Solubilization of water in mixed reverse micellar systems with anionic surfactant (AOT) and nonionic surfactants (Brijs, Spans, Tweens, Igepal CO 520), cationic surfactant (DDAB)–nonionic surfactants (Brijs, Spans, Igepal CO 520), and nonionic (Igepal CO 520)–nonionics (Brijs, Spans) in oils of different chemical structures and physical properties (isopropyl myristate, isobutyl benzene, cyclohexane) has been studied at 303 K. The enhancement in water solubilization has been evidenced in these systems with some exceptions. The maximum water solubilization capacity (ω 0, max) in mixed reverse micellar systems occurred at a certain mole fraction of a nonionic surfactant, which is indicated as X nonionic, max. The addition of electrolyte (NaCl or NaBr) in these systems tends to enhance their solubilization capacities further both at a fixed composition of nonionic (X nonionic; 0.1) and at X nonionic, max at 303 K …