Introduction São Tomé and Príncipe, a small island nation located in the Gulf of Guinea off the western coast of Central Africa, has developed a social security system that reflects its unique historical, political, and socioeconomic context. From colonial influences to post-independence reforms and contemporary challenges, the evolution of social protection in this African microstate illustrates broader themes of development economics, governance, and social welfare policy in small island developing states (SIDS). This analysis examines the formation and reforms of São Tomé and Príncipe’s social security system, highlighting key milestones, structural elements, and ongoing transformation efforts. Historical Context and Colonial Legacy Portuguese Colonial Period (until 1975) São Tomé and Príncipe’s earliest social protection mechanisms were established during Portuguese colonial rule, which lasted until independence in 1975. The colonial social security framework was highly restricted, primarily serving Portuguese settlers and a small number of local civil servants. The plantation economy (roças)...