Structural and kinetic aspects of the solubilization of phosphatidylcholine (PC) liposomes induced by the nonionic surfactant octyl glucoside (OG) and the reconstitution of PC vesicles by dilution of OG/PC mixed micellar systems were studied using dynamic light scattering and freeze-fracture electron microscopy. To this end, three regions were delimited in the equilibrium phase diagram. of this interaction: a "vesicular" region formed only by mixed vesicles, a "coexistence" region, in which fragmented vesicles and mixed micelles coexisted, and a "micellar" region formed by only mixed micelles. A simple mechanism of liposomes solubilization is proposed based on the following points: (a) Up to saturation of vesicles by OG, a direct formation of mixed micelles within the bilayer occurred. (b) The progressive separation of the formed micelles from the liposome. surface led to the complete solubilization of vesicles. (c) This separation would take place without formation of complex intermediate aggregates in equilibrated systems with the only presence of mixed micelles and fragmented vesicles. The systems placed in the micellar and vesicular regions were more stable with time than those placed in the coexistence region in which a growth of the fragmented vesicles and a reduction in their proportion were detected. The dilution (one step fast dilution) of OG/PC micellar solutions placed on the micellar phase boundary (corresponding to the effective surfactant to PC molar ratio for liposome solubilization, Re-SOL) led to the formation of vesicles, in which the higher the total concentration of OG and PC in the initial system, the higher the size of the reconstituted vesicles. The kinetics of solubilization and reconstitution processes showed that the "induction time" (time needed for the processes to start) for the formation mixed micelles was higher that for the reconstitution of mixed vesicles, indicating that the reconstitution process was faster than that of solubilization.