Community-based strategies play a significant role in many health systems in low- and middle-income countries, especially in light of critical shortages in the health workforce. The term community health worker has been used to refer to volunteers and salaried, professional or lay health workers with a wide range of training, experience, scope of practice and integration in health systems. In the context of this study, we use the term community-based practitioner (CBPs) to reflect the diverse nature of these cadres of health workers. CBPs provide preventive, promotive, curative and palliative services across a range of areas, including reproductive, maternal, newborn and child health, HIV, tuberculosis, malaria, control of other endemic diseases, and noncommunicable diseases. Significant evidence has emerged over the past two decades on their effectiveness, which has triggered interest in the potential to use their services to expand access to care, in particular in rural and underserved areas where deployment and retention of more qualified health workers is problematic. Calls have been made to integrate CBP programmes in human resources and health strategies, and to scale up rapidly the extent and coverage of CBP initiatives.