Abstract.This review examines emergencies that occur prior to, during, or immediately after endodontic treatment. The range of treatments, from very little to a great deal, are discussed in relation to irreversibly damaged vital pulps, necrotic pulps and alveolar abscesses. It is concluded that there has been a significant trend towards effective treatment of the emergency by complete instrumentation and sealing of the coronal access at the initial appointment. The need to clean the root canal system and prevent its subsequent infection by the oral flora is stressed.