Stephen A. Webb is Professor of Social Work, Glasgow Caledonian University, UK. Recent books include Evidence-based Social Work (with Gray & Plath, Routledge 2009), Social Work Theories and Methods (with Gray, Sage 2013), and the Sage Handbook of Social Work (with Gray & Midgley, 2012). Webb's critical analysis 'Considerations on the validity of evidence-based practice in social work' (2001) is the world's most cited article in the field and the most influential publication in social work over the last ten years (Hodges et al., 2011). Mel Gray is Professor of Social Work and Research Professor in the Research Institute of Advanced Study for Humanity at the University of Newcastle, Australia. She is Joint Editor of Australian Social Work and is on the editorial boards for several international journals. Her interests range from creativity, morality, spirituality and theory and philosophy in social work to experiential social work education.