Book excerpt: This groundbreaking examination of cybersex was originally published as a special issue of the journal Sexual Addiction and Compulsivity. It is a crucial resource for sex therapists, who until now had no rigorous study of the effect of online pornography on the patients they treat. It will also be of great interest to general marriage and family therapists who find themselves dealing with this issue with their clients, as well as others who are interested in the Internet as a social phenomenon. Cybersex: The Dark Side of the Force presents for the first time an empirical foundation for the discussion of cybersex compulsivity and its effect on the mental health of individuals, couples, teens, and young children.