Traditional ＇business as usual＇ financing methods will no longer be adequate to meet the unprecedented demands for capital to finance energy sector expansion in the developing countries. In recognition, many countries are opening up their power sectors to private investment, initially through the establishment of independent power projects, but in some cases through sector privatization. Project financing has many advantages, but further sectoral reorganization, including tariff reform, will be needed to attract resources on the scale required, especially from domestic investors. In oil and gas, in contrast to power, private capital from the international oil companies has always played a major role in the developing countries, However, sharply increasing investment requirements require a growing role for external finance. There should, in principle, be no shortage of investible funds to finance energy sector expansion in developing countries so long as host countries establish conditions which are attractive to private investors. The augmented role of private finance requires a continuing, if different, role for the public sector in both host countries and official aid agencies.