The stratum corneum is a magnificent example of the successful adaptation of a tissue. Its efficient function is a prerequisite for life itself. We depend on its control of the movement of water through the skin and on its protective role in the prevention of penetration by pathogens or harmful substances. Apart from its functional importance, there is no escaping the fact that the most common skin disorders (psoriasis, eczema, inherited disorders of keratinization, acne) are 'characterised by abnormal keratinization and or scaliness. Despite all this, understanding of its chemistry, structure, physiology and involvement in disease has been sadly deficient; however, there are signs of enlightenment. This symposium is evidence of changed atti· tudes. Leading researchers from many countries have applied modem biomedical techniques and the methods of molecular biology to the many problems and questions posed by the stratum corneum. Although there have been several symposia and publications on the process of keratinization, few have been broadly based on the stratum corneum. For this reason we believe that the proceedings of this symposium will be invaluable for all who are profeSSionally concerned with skin biology. Cardiff/Diisseldorf, November 1982 R. Marks G. Plewig v Acknowledgements Alcon Labs. Limited Brocades G. B. Limited Cardiff City Council Cassella-Riedel Pharma GmbH. Cilag-Chemie Dermal Laboratories Limited Dista Products Limited Dome Div. Miles Laboratories Limited Hoechst AG. Imperial Chemical Industries Limited Janssen Pharmaceuticals Limited Johnson & Johnson Limited L'Oreal E.