This article examines neighborhood-level factors to help explain why adolescent birth rate trajectories differ in certain communities in California, with rates in some areas remaining elevated or increasing while rates in other areas with similar demographic characteristics declined. Researchers conducted in-depth interviews with 94 community stakeholders and 22 focus groups with 186 adolescents from five "promising" communities (with declining adolescent birth rates) and five "struggling" communities (persistently elevated or increasing rates). Promising communities had more employment prospects, better neighbor interactions, and greater educational opportunities for youth. Parent–child communication around sex and youth knowledge of clinics were also more common. In contrast, struggling communities tended to have higher perceived levels of crime and poverty and more negative attitudes toward youth. These findings illustrate the complexity of factors that influence adolescents’ lives and decision-making. Synergistic community-based approaches to adolescent health and development are critical to promote positive health outcomes.