Introduction Reduction of aggression rate is a major challenge in acute inpatient psychiatric units and may adversely affect the wellbeing of both staff and patients The lifetime risk for assault on nurses working on inpatient psychiatric units has been reported to be approximately The efficacy of current risk assessment strategies in lowering incidence of violence on acute inpatient psychiatry units is still unclear Methods Electronic Medical Records were retrospectively reviewed for violent and aggressive incidents reported by the staff over a six month period in acute inpatient adult psychiatry units Results A total of aggressive incidents were reported of which were patient on patient and patient on staff The highest risk factors for being involved in an aggressive incident included a male gender b schizoaffective and schizophrenia diagnosis c substance use disorder Approximately of patients involved in aggressive actions had a secondary diagnosis of substance use disorders Conclusion The data suggest that the majority of aggressive behaviors on inpatient units are patient on patient At least of the individuals involved in aggressive behavior have a secondary diagnosis of substance use disorder