Using qualitative data, this article explored the circumstances leading to HIV testing among 59 HIV-infected adolescents recruited from New York City HIV clinics. Results showed differences between the heterosexual women and the gay and bisexual men. Most of the young women were tested during routine health care or self-initiated tests, and most were asymptomatic when they tested positive. Their testing decisions were sometimes based on assessments of their boyfriends' risk behaviors rather than their own. Many young men were experiencing symptoms of illness when they tested positive, and about half of them recognized their symptoms as related to HIV and sought tests. Some young men expressed fear of learning about positive test results, which delayed their testing, and some providers did not initially recommend HIV testing for young men who presented with symptoms. The article concludes that consideration of these gender and sexual orientation-related concerns can facilitate HIV testing among adolescents.