The aim of this paper was to provide an update on necrotizing periodontal disease (NPD). Original papers on this subject published in English from January 2002 until December 2007 were located in MEDLINE/PubMed database. Other sources were taken from the references of the selected papers. The clinical features of NPD include necrosis and ulceration of the gingival margin and the interdental papilla. These signs are usually associated to halitosis, pain, spontaneous gingival bleeding, malaise and sometimes fever. NPD usually occurs in developing countries, but few cases have also been reported in industrialized nations. The predisposing factors associated with the onset and progression of NPD include immunodeficiency, malnutrition, stress, smoking and poor oral hygiene. The treatment of NPD is dependent on the presence of pain and gingival necrosis. Systemic antibiotic therapy is recommended when a systemic disease is suspected.