When it comes to the reproductive health behaviors of teens and young adults, far more public attention has focused on women than on men. That's not surprising. After all, men don't actually have the babies. Yet the importance of understanding men's reproductive health behaviors should not be overlooked, given their potential implications for men themselves, as well as for their sexual partners and for children. For example, risky sexual behaviors may lead to an unintended pregnancy or to acquiring a sexually transmitted infection (STI). As it is, STI rates are high in the United States, and teens and young adults (aged 15-24) account for one-half of new STI diagnoses. Thus, it is particularly important to examine reproductive health behaviors among men in this age group. It is important for other reasons as well. Men who father children at a young age are less likely than are other fathers to marry the mother of their child, and these young fathers have lower educational attainment and earnings than do older fathers. Moreover, children of young parents or children who result from unwanted pregnancies face economic disadvantage and have lower cognitive attainment and greater behavioral problems than do other children. Recent data allow us to develop better insights into men's reproductive behaviors and motivations. This "Research Brief" draws on the male data file from the 2002 National Survey of Family Growth to present a descriptive portrait of reproductive health behavior among U.S. teen and young adult men. To develop this portrait, we examined survey results on several dimensions of reproductive health by age and by race/ethnicity. Specifically, we looked at nationally representative data for men between the ages of 15 and 24 related to sexual experience and activity, access to reproductive health services, condom use and motivation, and fertility. Results of our analyses show that levels of recent sexual activity are fairly low, especially among teen men. However, we also found that receipt of reproductive health services among men--even among those who are sexually experienced--is also low, which is a cause for concern. Among other findings derived from our analyses was that more men reported that they use condoms for pregnancy prevention than to ward against disease. (Contains 8 figures.)