This report examines workers known to have sustained an injury of such severity that they were admitted to a hospital for medical treatment. The report is based on hospital separation data supplied by the Australian Institute of Health and Welfare (AIHW) from the National Hospital Morbidity Database (NHMD). A hospital separation occurs when an episode of care for an admitted patient ceases. Since a person may have had more than one period of hospitalisation during the period July 2006 to June 2009 hospitalisation counts are not counts of individuals.