The book documents the history of the prevention-of-mother-to child transmission of HIV (PMTCT) program in Guyana, as well as the impact of HIV on pregnant and postpartum women’s adherence to antiretroviral therapy (ART). The book shows research work by reviewing the literature to investigate relevant adherence studies, presenting in-depth interviews on adherence perspectives of clinic patients and healthcare providers, and a cross-sectional descriptive study of pregnant women that investigated general adherence to pregnancy-related behaviours and ART, and the efficacy of a theoretical model (Health Belief Model) to understand and predict ART adherence within this group. Author discusses the factors affecting ART adherence among pregnant and postpartum women, since existing studies may not account for cultural and other local variations. The findings provide insight into the local situation, and will also inform policy and practice in Guyana, and the wider Caribbean Community (CARICOM).