Out of control sexual behavior, also known as compulsive sexual behavior or sexual addiction, has not been studied in a representative sample of the general population. At age 32 years, 940 (93%) of 1,015 members of the birth cohort of the Dunedin Multidisciplinary Health and Development Study responded to a series of questions about sexual behavior, administered by computer. We enquired about sexual fantasies, urges or behavior that participants regarded as out of control during the previous year, and defined such experiences as out of control sexual experiences (OCSE). Nearly 13% of men and 7% of women reported OCSE in the past year. Women who reported such experiences were more likely than other women to have reported (elsewhere in the interview) having had high numbers of opposite sex partners, concurrent sexual relationships, or sex with a partner met on the internet, as well as a higher likelihood of same-sex attraction or behavior. Among men reporting OCSE, there was an association with having paid for heterosexual sex and with same-sex attraction and behavior. Few believed that OCSE had interfered with their lives (3.8% of all men and 1.7% of all women in the cohort). Only 0.8% of men and 0.6% of women reported that their actual sexual behavior had interfered with their lives. OCSE were also analyzed in relation to certain personality traits and to childhood sexual abuse (CSA). Some evidence of a link with impulsivity (women only) and negative affectivity was found. CSA was associated with OCSE among men. In conclusion, this population-based study has provided the first empirical estimations of the occurrence of OCSE and its relationship to a range of sexual behaviors in a representative sample.