The Indo-US 123 agreement will allow nuclear energy to become a vital part in India’s domestic energy supply. Nuclear energy could provide India 35% of its energy supply by 2050, reducing its CO2 emissions. It will substitute for the energy baseline which has been fossil-fuel based until now. India is the third highest CO2 emitter globally and the role of nuclear energy as a baseline will be vital to CO2 emission reduction goals. Foreign involvement in the Indian nuclear sector will aid the development of India’s three-stage programme, which will help to sustain its growing energy demand. In addition to providing an alternate baseline to coal, nuclear energy will increase domestic self-sustainability and reduce dependence on fossil fuels in a cost-effective manner. As a combination of multiple efforts, domestic, bi-lateral and international, the nuclear energy transition will assume an important role in India and this represents successful global environmental policy.