Developments in information technology offer new opportunities to design electronic patient record systems (EPR) which integrate a broad range of functions such as clinical decision support, order entry, or electronic alerts. It has been recently suggested that EPR could support new applications for disease surveillance and patient safety. We describe the integration of a voluntary incident reporting system into an EPR used in operating theatres, to allow the reporting of accidents and preventable complications. We assessed system's reliability and users' acceptance. During the 4-years observation period (2002-2006), 48,983 interventional procedures were performed. Clinicians documented 85.1% of procedures on the incident reporting form. Agreement between chart review and electronically reported incidents was 80.6%. The integration of an incident reporting system into an EPR is reliable and well supported by health care professionals.