Chapter 5 explores the role of social institutions in human rights implementation by way of a case study. Using the example of Islamic law and organisations as social institutions, the study examines their role in implementing women’s right to family planning in Indonesia. The study exposes the ways in which Islamic law and organisations were involved in Indonesia’s family planning programme, and assesses their role and contribution as perceived by local actors. Chapter 5 pays special attention to the agency of Muslim reformists (particularly ‘Muslim feminists’) in offering reinterpretations of Islamic law that promote women’s health and equality. The study concludes that Islam was instrumental to the programme’s success, and reflects normatively on whether/to what extent states should engage social institutions in implementing their human rights treaty obligations. The chapter then evaluates and critiques the approach to Islam taken by the UN treaty bodies in their supervision of Indonesia’s domestic implementation.