Helping clients to develop alternative and more constructive viewpoints to tackle their problems lies at the heart of cognitive behaviour therapy (CBT). This development is facilitated by the quality of the argument- not to be confused with arguing- that therapists present to their clients. Students as well as experienced practitioners frequently complain that they are "stuck" when confronted with some clients' self-defeating thoughts and beliefs; they lack or cannot think of good and persuasive arguments to put forward at the time.The purpose of this book is to provide therapists with ideas and arguments they can present to and build on in their discussions with clients. This book represents an addition to the therapist's "argumentarium" in the same way that new techniques are added to the therapist's armamentarium. It will appeal not only to cognitive behavioural practitioners, novice and experienced alike, but also to every therapist who wants to improve their current repertoire of rational arguments to promote client change.