Steven C. Hayes is Nevada Foundation Professor at the Department of Psychology at the University of Nevada. Frank W. Bond is Professor of Work Psychology at Goldsmiths College, University of London, and he trained both as a clinical and work psychologist. Dermot Barnes-Holmes s is foundation Professor and Head of the Department of Psychology at the National University of Ireland. John Austin is currently Associate Professor in Psychology in the Industrial-Organizational Psychology and Applied Behavior Analysis programs at Western Michigan University.