We all indulge in risky behaviour and weigh up the benefits and possible bad effects in various ways, depending on personality and experience. Health professionals have to convey the notion of risk in such a way that patients may understand the choices they face. Different people will react in different ways to risk data, thus communication needs to be individually tailored to take into account how patients handle figures and what they are prepared to gain or lose. Only if a patient fully understands the risks he or she faces can they truly give informed consent. In the past, the paternalistic doctor often gave minimal information about risk in order to shield the patient from worry. This behaviour is no longer acceptable as patients have a legal as well as a moral right to understand their illness and the possible benefits or adverse risks of treatment options.