The concept of sexual deviance refers to the nature of sexual behavior that is nonconforming with societal norms or expectations, is maladaptive and interferes with the individuals functioning. Sexual deviance is also often perceived as harmful or even dangerous. In most cases, it manifests through the use of force, sexual focus on children or other anomalous activities and targets. It encompasses a vast range of atypical or aberrant sexual behaviors that may or may not be formalised into a law. The author of this book adheres to the theory that although sexual violence may be motivated by opportunistic factors, the common denominator in most instances of sexual abuse is sexual deviance. The results of the authors' research indicate that most male and female subjects interpret sexual deviance as a multi-causal phenomenon; however, juvenile sex offenders are more likely to externalise these causes rather than attribute them to internal factors. This book is divided into three major parts. The first part focuses on critical review of different theories of etiology of sexual deviance, sex offender characteristics and treatment implications; the second explores attribution of sexually abnormal behavior and its measurement; and the third describes the findings of the study and their relevance to the treatment of sexual abusers.