The study was based on a two-page survey instrument sent to high school students around the United States. Commercial lists of high school students nationally were identified. A composite list of more than eight million names and home addresses from among approximately 15 million high school students in the country was used to draw a random national sample of 20,000, stratified by juniors and seniors. In April 2000, surveys were mailed to 20,000 students at their home addresses. A follow-up, first-class postcard to 5,000 students for whom we still maintained access to their names was mailed one-week after the survey mailing encouraged students to respond. The mailing lists were destroyed following this one-time use for research purposes only. The post office returned as undeliverable 5.46 percent of the original surveys. We therefore assumed that at most 18,600 arrived at their destination. We received in the mail 1,541 completed, useable surveys. The sample, therefore, reflects an 8.28 percent response rate.