How is human love deformed in sexual addiction? How can human love be transformed? David Bellusci considers three signs of addiction and then, by looking at neurotic tendencies within a psychoanalytical framework, as well as the neurobiological nature of sexual pleasure, explores the causes of sexual addiction. Behavioral expression of addiction is examined in pornography, masturbation, cybersex, and multiple sexual partners. Working within a Christian anthropology drawn from Thomas Aquinas, Bellusci considers the morality of pleasure; how pleasure suggests an antinomy of satisfaction-dissatisfaction. He explores how the fallen human condition effects the will, and the consent to sin. He concludes with a focus on how the addict may be supported, at the psychological, relational, and spiritual levels.