Aaron T Beck is one of the `founding fathers' of the cognitive revolution in psychotherapy. His Cognitive Therapy was innovative in its emphasis on the role of cognition in emotional distress and behavioural dysfunction. Beck first established his reputation in the field of depression. However, Cognitive Therapy has now grown in scope to address a number of disorders and health problems - both clinical and nonclinical - and today Beck's work exercises an enormous influence on psychotherapy in general. This book presents a unique overview of Beck's life and his theoretical and practical achievements. The author considers and effectively rebuts the criticisms that his ideas have attracted over the years and discusses Beck's continuing influence on the research and practice of Cognitive Therapy.