Not much is known about the etiology, or development, of deviant sexual interests. The aim of this systematic review was to provide a broad overview of current theories on the etiology of sexual deviance. We conducted a systematic search of the databases PubMed and APA PsycInfo (EBSCO). Studies were included when they discussed a theory regarding the etiology or development of sexual deviance. Included studies were
assessed on quality criteria for good theories. Common etiological themes were extracted using thematic analysis. We included 47 theories explaining sexual deviance in general as well as various specific deviant sexual interests, such as pedophilia and sadism/masochism. Few theories (k = 7) were of acceptable quality as suggested by our systematic assessment of quality criteria for good theories (QUACGOT). These theories indicated that deviant sexual interests may develop as the result of an interplay of various factors: excitation transfer between emotions and sexual arousal, conditioning, problems with “normative” sexuality, and social learning. Neurobiological findings could not be included as no acceptable quality neurobiological theories could be retrieved. The important roles of excitation transfer and conditioning designate that dynamic, changeable processes take part in the etiology of sexual deviance. These same processes could potentially be deployed to diminish unwanted deviant sexual interests.