The increasing number of individuals and couples seeking help for psychosexual difficulties presents a challenge to the helping profes sions. Although considerable progress has been made over the past twenty years in the development of therapy approaches, there remains a significant proportion of cases who fail to respond to treatment or whose improvement in sexual functioning is short-lived. It is suggested that such limitations of therapy reflect our lack of understanding of the psychosocial determinants of sexual responding. Whereas the biological determinants are now well understood, much less is known about the psychosocial factors which influence sexual responding. The aim of this book is to examine in depth some of the psychosocial factors which must be considered during the assessment and treatment of psychosexual dysfunction. It has been written for those helping professionals who already have expertise in cognitive behavioural assessment and therapy. Although much of the text focuses on practical issues, reference is made to empirical evidence regarding the determinants of sexual functioning and effectiveness of therapy methods. A scientist-practitioner approach is followed wherever possible, combined with practical illustrations from the author's own clinical work.