In a collaboration between SeRC researchers at SU, KTH, and KI as well as ERCO Pharma AB, we have developed new computational methods to fit molecular data to cryo-EM image data of vitreous sections (CEMOVIS) of skin. This has made it possible to develop much more detailed models of the structure of skin, in particular how the outer horny layer (stratum corneum) is formed by lipids changing from cubic to lamellar phases. This has led to a completely new type of studies where CEMOVIS data and simulations complement each other, which in turn has enabled us to perform the first accurate molecular simulations of the permeability of skin to a whole range of compounds as well as effects of permeation enhancers, which is an extremely important topic for the pharmaceutical industry to make it possible to design new drugs delivered by transdermal patches. [Lundborg, J Control. Rel. 283, 269; Wennberg, Biophys J 114, 1116]