This study of the contextual aspects of adolescent girls, sexual behavior examines the role of choice by adolescent girls, regarding their first time ever sex. In addition the study explores the factors that contribute to girls, choice to have sex for the first time. Narrative analysis, using semi-structured interviews with open-ended questions, was used to interview seventeen sexually active girls ages fourteen to nineteen. The analysis, conducted with a feminist perspective, revealed that girls perceived they exercised choice regarding first time ever sex and that they developed moral codes to determine the subjective rightness or wrongness of having sex with a boy. The following criteria rendered having sex with a boy the “right” thing to do: (1) the length of relationship, (2) the boy's “being there” for the girl, (3) the girl's feeling of love toward the boy, (4) the girl's trusting the boy, (5) the girl's sense that this was the right boy and the right time for her to have sex, (6) the girl's curiosity about sex, and (7) the girl's taking precautions to maintain herself infection-free during sex. Analysis also revealed that girls had a partial and superficial understanding of taking precautions to maintain themselves free from infection. Ten of the thirteen girls who used condoms during their first time sexual experience abandoned using condoms during subsequent sexual intercourse with the same boyfriend. Younger girls did not use condoms to protect themselves from infection. First time sex with boys paved the way for the girls to trust the boys not to give them infections during subsequent sexual activity. Some girls relied on medical documentation that stated the boy was “clean,” and girls believed that the documentation was valid for the duration of the relationship the girls had with the boys. Key implications include the need for (1) sex education to pre-adolescent girls prior to girls becoming sexually active, (2) addressing the gaps and misunderstandings regarding sexual disease transmission, (3) accurate and complete instruction about disease prevention, and (4) training practitioners to take accurate sexual histories and to be alert to misunderstandings about disease transmission.