The 4th edition of the "Braun-Falco Textbook", an international standard text of dermatology, allergy and sexually transmitted disorders has been thoroughly rewritten and reedited and offers a comprehensive state-of-the-art review of the entire field for clinicians in hospital and private practice. New aspects of the 4th edition that reflect the tremendous and rapid progress of dermatology include an up to date clinical classification of dermatoses, current guidelines and therapeutic concepts in inflammatory and neoplastic diseases, and dermatological aspects of the new Covid-19 infection. prev. ed.: 2008.