Aim: The overall aim is to assess the appropriateness of Lay Health Worker (LHW)programmes as a public health intervention in South Africa by considering the effectivenessof LHW programmes across the world and the experience of LHW programmeimplementation and policy making in South Africa. Methods: This thesis comprises 4 papers that explore the issue of LHWs: (I) A systematicreview of randomised controlled trials (RCTs) of LHW interventions in primary andcommunity health care for maternal and child health and the management of infectiousdiseases; (II) A study of the experiences of farm dwellers trained to be LHWs, as exploredthrough focus group discussions; (III) A study of three LHW supervisors who worked on anintervention to support infant feeding mothers, as explored through individual interviews;and (IV) A study of the process of LHW policy development from the perspective of 11 keyinformants who were individually interviewed. Findings: LHWs were found to be effective in promoting breastfeeding and in improvingpulmonary TB cure rates (I). There was also some indication that LHWs could be effective inreducing child morbidity and child and neonatal mortality, and in increasing the likelihood ofcaregivers seeking care for childhood illness (I). The experience of LHWs and LHWsupervisors suggests that LHW programmes need adequate support and supervision,especially in protecting the LHWs themselves (II, III). The care and protection of LHWs wasconsidered by policy makers (IV), but policy redevelopment processes did not link the needto ensure that LHWs were not exploited to concerns about gender exploitation. Conclusions: LHW interventions can be effective but implementing them in developingcountries such as South Africa needs to be approached with caution