The hypothesis that parental communication and monitoring of adolescent children will discourage premarital sexual activity is examined among white 15 and 16-year-olds interviewed in the 1981 US National Survey of Children the 2nd wave of a nationally representative longitudinal study designed to assess the physical social and psychological well-being of different groups of US children. Whites were studied separately since preliminary analysis indicates different factors contributing to sexual behavior in black and white adolescents. Interview data were collected not only from young persons but also from the most knowledgeable custodial parent--usually the mother; for whom an attempt was made to measure attitudes on divorce division of labor in a family maternal emplloyment and marriage; and parental monitoring of adolescents expressed in terms of the proportion of childs friends known and communication on sex lifestyle and general issues. A parental assessment of neighborhood quality was included as well. Analyses indicate little support for the study hypothesis in the total sample. Only 2 of 10 comparisons show variations that are statistically significant: knowing friends of females p<.05 1 tailed t-test and neighborhood assessment by parents of males p<.01 when the sample is partitioned according to a measure of parental traditional attitudes 1 group--the daughters of traditional parents who have communicated with then about sex of about television--are found less likely to have had intercourse at p<.01 there is no overall efect of parent traditionality among son. It is possible few parents initiate discussions about sex with sons until evidence of sexual activity leads parents especially traditional parents to do so a fact suggested by the higher incidence of premarital sexual activity among sons of traditional parents who have discussed sex with their parents.