Risk assessment has always been an essential part of all medical practice, and doctors have always been trained to make rapid assessment of risk. Much of the early training of doctors in both medicine and surgery centres on risk assessment. However, the method of acquiring that knowledge is predominantly through the apprenticeship model with observation by the trainee of the trainer's decision-making process. Those decisions, however, are often skewed and biased by a whole variety of influences, rather than always being based on scientific evidence. Clearly the increasing influence of evidence-based medicine will help this. At one extreme, however, there are heroic surgeons taking unnecessary risk or taking on cases which might more appropriately have been left without treatment, and at the other extreme, consultants who may feel demoralised or depressed might well become nihilistic about medicine and therefore might not attempt to treat cases that are treatable.