In many developing countries, services to prevent the mother-to-child transmission (PMTCT) of human immunodeficiency virus (HIV) operate with limited contact with HIV care and treatment programs, despite significant advances in the accessibility of both services. There is a need to deliver more complex multidrug PMTCT interventions that extend beyond single-dose nevirapine, particularly for pregnant women with advanced HIV disease who are at high risk of transmitting HIV to their children and require rapid initiation of life-long highly active antiretroviral therapy. We argue for strengthened ties between PMTCT services and HIV care and treatment programs in resource-limited settings, viewing PMTCT programs as a gateway to family-based HIV care and treatment. Existing experiences from the multicountry MTCT-Plus Initiative suggest that close ties between PMTCT services and HIV care and treatment programs are feasible and can lead to significant advances in reducing the vertical transmission of HIV and promoting the health of HIV-infected women, children, and families.