The accurate assessment of risky sexual behaviors and barriers to condom use is essential to reduce the spread of HIV/AIDS. This study tests a new nonverbal response-card method for obtaining more accurate responses to sensitive questions in the context of face-to-face interviewer-administered questionnaires in a survey of 1,269 Ethiopian young people aged 13–24. Comparisons of responses between a control group that provided verbal responses and an experimental group that used the card indicate that the prevalence of nonmarital sexual intercourse may be two times higher and knowledge of condom access may be 22 percent lower in the study than typical population-survey methods suggest. These results suggest that our nonverbal response-card method yields less biased estimates of risky adolescent sexual behavior and perceived access to condoms than those derived from conventional face-to-face interviewer-administered surveys, and that this method provides an effective, easy-to-use, low-cost alternative.