Self-harm greatly increases the risk of subsequent suicide and the monitoring of self-harm is part of the National Suicide Prevention Strategy. The monitoring of self-harm locally enables us to measure the effectiveness of changes within the service and other interventions that impact on this group of patients. The Manchester Self-Harm (MaSH) Project is a city-wide collaboration between the University of Manchester and local hospitals. The project is funded by the Manchester Mental Health and Social Care NHS Trust. It began in April 1997 and data collection commenced in September 1997.