Before the Green Climate Fund (GCF) considers the role of the private sector in meeting the climate finance needs of developing countries, it should first ask: what are the needs of the people living in those countries as they confront the climate crisis, especially the poorest and most vulnerable? Second, can private finance and support for the private sector help to equitably and effectively meet those needs, in accordance with the GCF Governing Instrument and the United Nations Framework Convention on Climate Change? This report attempts to respond to these questions by de constructing ideological notions of “leveraging” and “crowding in” private finance and examining the track record of the private sector, private financiers and development finance institutions (DFIs) in developing countries. The report concludes that the GCF should approach private companies and financiers slowly and with a high degree of caution, and only engage them to the extent that they can guarantee compliance with high standards on environmental, social and development effectiveness; implement robust processes designed to address financial, social and environmental risks; and produce effective mitigation and adaptation outcomes.