Of the thousands of papers and books about problematic sexual behaviors, most focus solely on sex crimes or so-called "hyper-sexuality" or "sexual addiction." Together, these publications present a grim and pessimistic prognosis for anyone who has unusual sexual interests of any type. This book challenges that view by providing a more informed and balanced review of what is known and what is not known about unconventional sexual interests. It is based on approximately thirty years of experience by the author concerning the assessment and treatment of paraphilias and unconventional sexual interests. examines current and past perspectives concerning unconventional sexual interests associated with both criminal and non-criminal activities. Extensively referenced, it challenges the dogma that sexual interests are immutably determined during a single critical period and are thereafter unchangeable. The book provides extensive case histories and tables summarizing over 100 paraphilias and the latest research regarding them. It also reviews diagnostic criteria for the paraphilias. Analyses of current and past paradigms are presented together with new ways to understand, investigate, and provide meaningful and effective assistance to people with paraphilias. It is written for mental health clinicians and specialists in the fields of sexology and forensic psychiatry and psychology.