Angina bullosa haemorrhagica (ABH) is a relatively recently recognized bullous disorder in which recurrent oral blood blisters appear in the absence of any identified systemic disorder. This study has examined the clinical, histologic, immunologic, and hemostatic features of 30 British patients and demonstrates that ABH is predominantly a localized disorder of middle-aged or elderly patients of either sex that is evident mainly as blood blisters on the soft palate. Trauma appears to be the most common identifiable precipitating factor, but the essential tissue defect is as yet unidentified.