INTRODUCTION: Numerous barriers to optimal uptake of prevention of mother to child transmission (PMTCT) services occur at community level (i.e., outside the healthcare setting). To achieve elimination of paediatric HIV, therefore, interventions must also work within communities to address these barriers and increase service use and need to be informed by evidence. This paper reviews community-based approaches that have been used in resource-limited settings to increase rates of PMTCT enrolment, retention in care and successful treatment outcomes. It aims to identify which interventions work, why they may do so and what knowledge gaps remain. METHODS: First, we identified barriers to PMTCT that originate outside the health system. These were used to construct a social ecological framework categorizing barriers to PMTCT into the following levels of influence: individual, peer and family, community and sociocultural. We then used this conceptual framework to guide a review of the literature on community-based approaches, defined as interventions delivered outside of formal health settings, with the goal of increasing uptake, retention, adherence and positive psychosocial outcomes in PMTCT programmes in resource-poor countries. RESULTS: Our review found evidence of effectiveness of strategies targeting individuals and peer/family levels (e.g., providing household HIV testing and training peer counsellors to support exclusive breastfeeding) and at community level (e.g., participatory women's groups and home-based care to support adherence and retention). Evidence is more limited for complex interventions combining multiple strategies across different ecological levels. There is often little information describing implementation; and approaches such as "community mobilization" remain poorly defined. CONCLUSIONS: Evidence from existing community approaches can be adapted for use in planning PMTCT. However, for successful replication of evidence-based interventions to occur, comprehensive process evaluations are needed to elucidate the pathways through which specific interventions achieve desired PMTCT outcomes. A social ecological framework can help analyze the complex interplay of facilitators and barriers to PMTCT service uptake in each context, thus helping to inform selection of locally relevant community-based interventions.