True pemphigus is a group of autoimmune bullous dermatoses involving skin and mucosa and induced by IgG-autoantibodies. The article presents the mechanisms of the disease involving the target antigens of the intercellular substance of stratified epithelium. The clinical experience accumulated over the last 60 years and implementation of fundamental research methods in medical practice increased knowledge about the development and progression of autoimmune pemphigus. Clinical manifestations of both the conventional form of the disease and independent forms determined based on the pathogenetic factors were described in detail. The latter are represented by paraneoplastic and drug-induced forms of pemphigus. The authors emphasize that in-depth study of autoimmune pemphigus using various molecular biological research methods revealed pathogenetic relationships between various clinical manifestations of this bullous dermatosis and detected autoantibodies and target antigens. However, the true mechanism of this pathology, where antibodies cause loss of cell adhesion, is still not fully understood. This requires further thorough and comprehensive investigation of the disease.