Perioperative hypothermia is common and adversely affects clinical outcomes due to its effect on a range of homeostatic functions. Many of these adverse consequences are preventable by the use of warming techniques. A literature search was conducted to identify relevant published articles on perioperative hypothermia and warming. The databases searched include MEDLINE (1966 to February 2005), EMBASE (1974 to February 2005), CINAHL, the Cochrane library and the health technology assessment database. Reference lists of key articles were also searched. The primary beneficial effects of warming are mediated through increased blood flow and oxygen tension at tissue level. Reduction in wound infection, blood loss and perioperative pain with warming is promising. However, more evidence from good-quality prospective randomised controlled trials is needed to evaluate the role of warming in improving overall morbidity, mortality and hospital stay as well as to clarify its role as an adjunct to resuscitation and during the pre-hospital transport phase of critically ill patients. Awareness of the risks of perioperative hypothermia is the key to prevention. Achieving normothermia throughout the patient's journey is a worthwhile goal in surgical patients.