Background: The history of psoriasis, remains highly speculative for the time before Willan (1757-1812), and can be reliably assigned only for the last 200 years. Terms such as "Leprosy", "Impetigo" and "Psora" have been used in the centuries before. Hebra (1806-1880) gave a morphological and nosologic definition, in which also the histopathology appearance was taken into account. In the early 20th century, it was the biochemistry and histochemistry, which provided new insights. In the second half of the 20th century, immunocytochemistry and immunology shed some light on the pathogenetic processes of the disease. At the end of the 20th and at the beginning of the 21st century, it is the triumph of genetics and immunology, which have opened new therapeutic
possibilities due to the interesting insights into the pathogenesis of psoriasis. However besides the new therapeutic modalities, which harbor some health and some economic threats, classical approaches still remain valuable tools.