**1. Introduction**

The word "pemphigus" is derived from the Greek term "pemphix" meaning bubble or blister. Pemphigus is a group of autoimmune diseases (see Table 4) characterized by intra-epithelial blistering, resulting in superficial vesicles or bullae that easily rupture, resulting in ulceration of mucosal and/or cutaneous sites. Although rare, pemphigus causes significant morbidity and potential mortality for patients. The two main subtypes are pemphigus vulgaris (PV), and pemphigus foliaceous (PF), of which PV is the most common and clinically, the most aggressive variant, being associated with significant morbidity and mortality, composing 70% of all reported cases of pemphigus: Less common forms and variants include paraneoplastic pemphigus, drug induced pemphigus, and IgA pemphigus. This book chapter focuses on the diagnosis and treatment of PV and PF.
