The five papers which make up this special issue all reflect a feeling of guarded optimism about future applications of cognitive therapy in our clinical practice. A long way has been covered since the theoretical formulations of the early 60's, which led to the term “cognitive revolution” after Kuhn's (1962) exposé of how paradigm shifts occur in science. If there has been a revolution, it has been, on the whole, non-violent in spite of the sometimes shrill protests from the old guard. As Paul Salkovskis points out in the introductory paper, behaviour therapists have, perhaps paradoxically, been the most enthusiastic in coming to terms with the new paradigm. This coming to terms has involved experimental, theoretical and treatment studies. The areas covered have expanded steadily from depression and anxiety, to the obsessional disorders, the eating disorders, the phobias, adolescent problems and, as seen in this volume, to pain and marital conflict. Articles, books and new journals proliferate. Why should that be so?