Two years ago we implemented a reporting system for critical incidents in the Department of Anaesthesiology and Intensive Care of the University Hospital Dresden. During the first 18 months 162 anonymous reports were registered. The most common errors involved airway and ventilation management, followed by errors in fluid and cardio-vascular management. The main causes were distraction, lack of experience, specific training and communication deficits. The confidence in the anonymity of the reporting system was very high. Following the analysis of the reports, several modifications were initiated, e.g. specific training programs or definition of standards. Over time, a change in the relative distribution of reported errors was observed. The article discusses the different kinds of errors and possible countermeasures. It also strengthens several aspects which are important to consider during the initial phase of a local critical incident reporting system.