Cullen and Gathercole's review (B.A.B.P. Bull., 1976, Vol.4) of Mahoney's book, Cognition & Behaviour Modification, Ballinger, 1974, prompts me to take up my pen in defense of Mahoney and attack what I believe to be the unfortunate position that some radical behaviourists find themselves in. My reaction to Mahoney's book was very different from that of Cullen and Gathercole's. Fair enough, perhaps, as we each have our own standpoint on how cognitive behaviour modification is or should be. Nevertheless I feel some necessity to present my own views as I do not believe that Cullen and Gathercole's review did justice to the book as a whole. I found Mahoney's book to be an exciting and welcome departure from the current trend of books on behaviour therapy. It is not a review of existing behavioural techniques; nor an idiosyncratic view about what clinical practice should be. Mahoney has focussed carefully on one important and developing area in behaviour modification and provided a lucid, well-informed, thoughtful and at times amusing analysis of the clinical and experimental work pertinent to that area. Regardless of whether one accepts his conclusions or supports his theoretical position, I think the quality of the book should be recognised. Cullen and Gathercole spend most of their review discussing and rejecting Mahoney's theoretical views about mediational models. This is fair enough as their concern is primarily to demonstrate that such models are of little or no use in experimental or clinical psychology.