During baseline assessment, a computer questionnaire is administered, including questions about participants' attitudes, beliefs, and behaviors regarding sexual behavior, condom use, and drug use. A saliva sample is provided as well. A "Time-Line Follow-Back" is conducted, noting on which days certain activities occurred, such as sexual intercourse, alcohol use, marijuana use, and cigarette use. A urine sample is also collected in order to test for the STD's chlamydia and gonorrhea (if results are positive, we schedule a meeting with the participant to administer medication to treat the STD).