This publication describes a project to introduce a tool for self-evaluation by radiotherapy services that allows the analysis of errors or failures that might give rise to accidents. The results of applying this tool to a generic radiotherapy service are also presented. These results are used as a basis for a set of recommendations to strengthen quality and safety programmes in radiotherapy departments. Both operational experience (lessons learned from accidental exposure) and the results of probability safety assessment studies have been taken into account in applying the tool and formulating these recommendations.