Health care providers in low-income countries often treat consumers poorly. Many providers do not consider it their responsibility to listen carefully to consumer preferences, to facilitate access to care, to offer detailed information, or to treat patients with respect. A lack of provider accountability to health consumers may have adverse effects on the quality of health care they provide, and ultimately on health outcomes. This paper synthesizes relevant research on health provision in low-, middle- and high-income countries with the aim of identifying factors that shape health provider accountability to consumers, and discerning promising interventions to enhance responsiveness. Drawing on this scholarship, we develop a framework that classifies factors into two categories: those concerning the health system and those that pertain to social influences. Among the health systems factors that may shape provider accountability are oversight mechanisms, revenue sources, and the nature of competition in the health sector-all influences that may lead providers to be accountable to entities other than consumers, such as governments and donors. Among the social factors we explore are consumer power, especially information levels, and provider beliefs surrounding accountability. Evidence on factors and interventions shaping health provider accountability is thin. For this reason, it is not possible to draw firm conclusions on what works to enhance accountability. This being said, research does suggest four mechanisms that may improve provider responsiveness: 1. Creating official community participation mechanisms in the context of health service decentralization; 2. Enhancing the quality of health information that consumers receive; 3. Establishing community groups that empower consumers to take action; 4. Including non-governmental organizations in efforts to expand access to care. This synthesis reviews evidence on these and other interventions, and points to future research needs to build knowledge on how to enhance health provider accountability to consumers.