This study investigated age- and gender-specific associations between parental support and parental knowledge of the child's whereabouts, on the one hand, and sexual experience and sexual health (the ability to have safe and pleasurable sexual experiences) on the other hand. A representative Dutch sample of 1,263 males and 1,353 females (aged 12-25 years), who had previously engaged in sexual intercourse, completed a questionnaire that included measures of these constructs. Both parental support and knowledge were positively associated with contraceptive use, social skills in sexual interactions, sexual satisfaction, and delay of sexual debut. Findings also revealed that the majority of correlations between parental support and sexual experience and sexual health are attributable to the relationship between a supportive family environment and parental knowledge of the child's whereabouts. Parental knowledge thus appeared to be more important for healthy sexual development than parental support.