Today, a large and acrimonious public debate is in progress about pornography, children, and the Internet. In this article, findings are presented from a national survey of 1,501 Internet-using youth, 10- to 17-years-old, to address issues in the debate over children, pornography, and the Internet. Issues focused on consisted of: (1) do young people have extensive exposure to sexual materials over the Internet; (2) to what extent are young people’s exposures voluntary or involuntary; (3) does exposure cause any kind of harm; (4) is exposure confined to or specific to certain kinds of youth; (5) is exposure specific to certain kinds of activities; (6) does filtering and blocking appear effective; and (7) does parental supervision make any difference? Twenty-five percent of youth had unwanted exposure to sexual pictures on the Internet in the past year. Most youth had no negative reactions to their unwanted exposure, but one quarter said they were very or extremely upset. The use of filtering and blocking software was associated with a modest reduction in unwanted exposure. Forms of parental supervision were not associated with any reduction in exposure. Several study limitations are presented and discussed. The study illustrates the utility and urgency of more social science evidence to inform policy in this area. References