Many teenagers have unplanned, unwanted pregnancies. Research has shown that effective contraceptive use is hampered by a lack of knowledge and by negative attitudes. Providing accurate information does not necessarily lead to contraceptive use. This two-phase study attempted to assess contraceptive behavior, knowledge, and beliefs. In the first phase, four studies asked university students (N=505) about sexual activity, methods of contraception, past contraception education, sexual partners, natural family planning, sexual behavior attitudes, and knowledge of sexual myths. Thirty to 60 percent of respondents reported being ineffective users or nonusers of contraception. Reasons for ineffective use or nonuse included lack of a steady partner and infrequency of sexual intercourse. In the second phase of the study, an intervention method was attempted. Experimental subjects (N=74) were undergraduate women students; control subjects (N=78) were students in a human sexuality course and psychology students. Experimental subjects participated in a workshop covering the topics of risk of pregnancy, types of contraceptive methods, and effective use of contraception. In the second part of the workshop, women participated in behavioral-rehearsal tasks. Comparisons with control groups showed participation in the treatment significantly improved contraceptive responsibility. The combination of didactic information exchange, increased communication skills through behavioral rehearsal, and motivation by behavioral contracting seemed to be an effective intervention. (ABL)