The reduction of pre-operative anxiety in surgical patients is a routine part of nursing care, but much of the evidence which supports the view that high anxiety is related to worse recovery is based on ambiguous or unreliable indices of recovery. Instead, it has been argued that moderate levels of preoperative anxiety can help patients to prepare for surgery and reduce its stressfulness. On this basis, attempts to reduce anxiety would amount to the "medicalization" of a normal and useful state. Until recently little evidence supported this view, but research which has used hormonal changes to index surgical stress has provided evidence consistent with it. Alternative strategies for psychological preparation can be designed, which are not based on an attempt to reduce anxiety. However, attempts at psychological preparation of surgical patients pre-operatively should be regarded as experimental until more evidence is available about their effects on recovery.