Our scientific knowledge of pemphigus has dramatically progressed in recent years. However, despite the availability of various therapeutic options for the treatment of inflammatory diseases, only a few multicenter controlled trials have helped to define effective therapies in pemphigus. A major obstacle in comparing therapeutic outcomes between centers is the lack of generally accepted definitions and measurements for the clinical evaluation of patients with pemphigus. Common terms and end points of pemphigus are needed so that experts in the field can accurately measure and assess disease extent, activity, severity, and therapeutic response, and thus facilitate and advance clinical trials. This consensus statement from the International Pemphigus Committee represents 2 years of collaborative efforts to attain mutually acceptable common definitions for pemphigus. These should assist in development of consistent reporting of outcomes in future studies.