Some examples of systems including useful ingredients as cosurfactants and cosolventsto furnish suitable microemulsions to be applicated in technological fields such as cosmetics and dermopharmaceuticals, are given For systems with ionic surfactants, the usual cosurfactant (medium chain lenght alcohol) was substituted by more skin compatible ingredients as butyl lactate, or alternatively by oleic acid and a glycol as cosolvent mixed in the aqueous phase of the system. On the other hand, for a system with an alkyl glucoside as nonionic surfactant, temperature - insensitive microemulsions was obtained also with butyl lactate as cosurfactant. Moreover, the influence that the presence of glycols as cosolvents involve on the isotropic liquid regions of such systems has been also evidenced. In conclusion, it is possible to formulate suitable microemulsions to practical applications, overcoming the traditional problems of the most of the conventional microemulsions as are the biological agressivity of the cosurfactant for ionic surfactant systems, and the temperature dependence for nonionic surfactant systems.