The India–Bhutan relationship is perhaps the only bilateral engagement in South Asia, yielding high dividends to both parties. While Bhutan all through the years has appreciated India for its economic assistance, India, for its part, has been sensitive to Bhutan’s developmental needs. The relationship has helped Bhutan shape a unique developmental trajectory based on gross national happiness. Bhutan’s economy has grown substantially in recent years. However, the development cooperation between the two countries can be effectively divided into three significant waves. The first wave (1960s–1970s) focused on building the social and physical infrastructure. The second wave (1980s–1990s) saw substantive efforts towards democratisation and decentralisation. The third wave of the relationship focused on developing hydel projects, which has now expanded into other areas such as information technology, disaster risk management, education and research cooperation.