This paper, published by the T20 India Task Force, examines the challenges in mobilising private capital for climate action and proposes solutions to unlock flows at scale. Developing countries need USD one trillion per year in external finance for climate action by 2030. However, both real and perceived risks impede the mobilisation of private climate finance at scale. This policy brief proposes a framework of solutions for the G20 to make blended finance work for climate action and development by undertaking actions in three areas: (i) enabling environments; (ii) instruments; and (iii) institutions.