The timely communication of radiological findings is important for patient care. When imaging reveals abnormalities that require urgent action, or shows significant unexpected findings, the usual methods of communication may not be reliable enough to ensure that those responsible for clinical care of the patient act promptly. These guidelines suggest methods for improving communication in these circumstances, using clear protocols and procedures agreed between imaging units and referrers. Main Messages • Communicating critical radiological findings will enable urgent or appropriate action to be taken. • Good communication helps to improve patient safety. • Clear departmental protocols become familiar to referrers within the organisation. • Referrers should be aware of their responsibility to read and act on radiological reports.