Sexual behaviors and attitudes of female adolescents were studied as a function of age of boyfriend. Boyfriend's age was dichotomized: similar-aged was defined as within 2 years of the girls' age; older aged was 3 or more years older than the girl. A school-based, ethnically diverse sample of 9th-grade girls (N = 146) who had been in a serious romantic relationship was surveyed on 5 dimensions of sexual attitudes, 2 classes of sexual motives, 7 normative sexual behaviors, and 3 types of risky sexual practices. Results showed that in terms of behavior, girls with older boyfriends were more likely than girls with similar-aged boyfriends to engage in all forms of sexual intimacy, to have sex under the influence of alcohol or drugs, and to experience sexual coercion. In terms of sexual attitudes, girls with older boyfriends were more likely to endorse beliefs that guys are sexually driven, that sex "just happens" and is spontaneous, and that sex is related to maturity. These results are discussed in terms of a potential power differential that emerges when girls date older boys.