About the editor

CHARLES G. COSTELLO, PhD, is Emeritus Professor of Psychology,University of Calgary. Dr. Costello attended Manchester University,Durham University, and London University, from which he receivedhis doctorate in psychology in 1960.

In 1989, he was awarded The Psychologists' Association of AlbertaPresident's Award for Exceptional Contributions to the Disciplineof Psychology in Alberta. A prolific writer, he is the author ofmore than 90 published articles on a wide range of topics inpsychology. His other books include Symptoms of Psychopathology,Symptoms of Depression, Symptoms of Schizophrenia, Psychology forPsychiatrists (all from Wiley), and N=1: Experimental Investigationof the Individual Case (with P. O. Davidson).