This article reviews the literature on the subject of cervical cytological abnormalities in teenagers, defined as a Papanicolaou (Pap) smear result more severe than inflammation. There is discussion of the increasing prevalence of this problem in adolescents. Behavioral and biologic risk factors are examined. The role of the human papillomavirus, widely believed to be the etiologic agent, is addressed. Atypia, its relationship to cervical malignancies, and its management are reviewed. The possible role of the human immunodeficiency virus in the increasing prevalence of cytological abnormalities in teens is considered.