Regarded as the textbook of research on the effectiveness of counselling and psychotherapy, this volume is a favourite of practitioners who approach their work in an empirical spirit. While tracing research developments gradually as individual papers appear remains an important part of being well-informed about the field, the reviews and meta-analyses offered in this massive volume provide a very efficient entree into the research literature and a simple way of understanding the primary themes and tentative conclusions emerging from empirical research across the world. (Review originally published in 2003.)