The world is now well-used to terrorism, but doctors and the wider public are particularly shocked when those whose actions harm others are members of our profession. Unfortunately, the record shows that doctors are not strangers to such actions, and while few doctors deliberately harm their patients or others, we are drawn from the societies in which we live and share the characteristics of those societies. We may not know why individuals embark on harming others, and we certainly have no evidence-base for preventive action, but we should consider how the risks of such actions might be reduced. Possible actions include better selection for medical school, more liberal education during and after medical school, better supervision of professional aspects of training and correction of deficiencies, and closer scrutiny of untoward occurrences in medical practice. Our College, with its worldwide membership should support the development of such measures.