Over the past two decades, a widening gulf has emerged between illness presentation and the adequacy of traditional biomedical explanations. As a result, the causes of many illnesses remain a mystery for both patient and physician, with the consequence that increasing numbers of well-educated people are using alternative or complementary medicines. In an attempt to bridge this gap between illness and explanation, without sacrificing the clear benefits of the biomedical approach, many health care professionals have begun to consider a biophysiological approach. Central to this approach is the belief that disease and illness are not just the result of pathophysiological causes but involve and can be explained in terms of psychological and socio-cultural factors or causes.In this model, the beliefs held by the patient about their condition are considered central to the way they behave and respond to treatment. Such beliefs are not specific to patients, though they can greatly influence the behaviour and reasoning of health professionals as well. In addition, psychosocial influences in the form of beliefs have equal relevance for those in wider society regarding aetiology of illness, recovery and potential for treatment. This book is unique in examining the influence and power of beliefs, one of the key psychosocial factors considered to underpin and validate the biopsychosocial model. It brings together a range of experts from science to medicine to provide a unique account of the role and influence that beliefs can play in medicine.