Both NLC and SLN have many features that are advantageous for dermal application. They are colloidal carriers providing controlled release profiles for many substances. They are composed of physiological and biodegradable lipids exhibiting low toxicity and low cytotoxicity, that means an excellent tolerability. The small size ensures a close contact to the stratum corneum and can increase the amount of drug penetrated into the skin. Due to the occlusive properties of lipid nanoparticles, an increased skin hydration effect is observed. Furthermore, lipid nanoparticles are able to enhance the chemical stability of compounds sensitive to light, oxidation and hydrolysis. Enhancement of chemical stability after incorporation into lipid nanocarriers was proven for many cosmetic actives, e.g. coenzyme Q10, ascorbyl palmitate, tocopherol and retinol (Fig. 3)