While health care brings great benefits, all treatments, and many investigations, carry some risk. As patients, we should be told of the risks of specific treatments but we are also at risk from failings in the health care system itself. We suggest that, while there are many examples of individual health psychologists who have made important contributions, this has not yet translated into a broader disciplinary engagement. Health psychologists have devoted much more attention to patients and devoted much less attention to the potentially huge impact of studying and intervening with staff, clinical practice, and organizations. We believe that there are considerable opportunities for health psychology to engage more closely with patient safety and, more importantly, that this would be of great benefit to both patients and staff. Statement of contribution What is already known on this subject? While health care brings great benefits, all treatments, and many investigations, carry some risk. Patients are also at risk from failings in the health care system itself. Studies using review of medical records in many countries have found that between 8% and 12% of patients in hospital suffer an unintended harm due to health care. What does this study add? There are many examples of individual psychologists who have made important contributions, but this has not yet translated into a broader disciplinary engagement. There are considerable opportunities for health psychology to engage more closely with patient safety. These include health behaviour change, teamwork, communication after medical error, diagnosis and decision making, organisational culture, and improving compliance with rules and standards. Psychologists providing a clinical service to specialist services in any area could expand their remit from supporting patients to a more general support and engagement with safety and quality initiatives. Health psychologists have models to understand the behaviour of people, and recent developments in changing behaviour should be applicable to health professionals in addition to their patients.