The urgency to scale-up sustainable programs for the prevention of mother-to-child transmission of HIV (PMTCT) prompted priority countries of the Global Plan Toward the Elimination of New HIV Infections Among Children by 2015 and Keeping Their Mothers Alive (Global Plan) to expand the delivery of PMTCT services through greater integration with sexual and reproductive health and child health services. Countries approached integration—what, where, and how services are provided—in diverse ways, with predominantly favorable results. Approaches to integrated services have increased access to a broader range of PMTCT interventions, and they also have proved to be largely acceptable to clients and providers. The integration of PMTCT interventions with maternal, newborn, and child health settings was supported by strategies to reconfigure service delivery to provide additional services, including shifting tasks to nurses (such as initiating antiretroviral therapy and providing long-term follow-up). This was complemented by supporting community outreach and integrating HIV and sexual and reproductive health services bidirectionally, including by providing family planning through antiretroviral therapy clinics and HIV testing in family planning clinics. A systematic and rigorous study of country experiences integrating HIV and maternal, newborn, and child health services, including maternal and pediatric TB services, cost analysis, could provide valuable lessons and demonstrate how such integration can improve systems for health care delivery.