Geoffrey Harcourt remained a steadfast left Keynesian all his life. He applied his economic analysis in framing policy recommendations targeting the welfare of the poor. He undertook incisive and comprehensive surveys of the work of Cambridge post-Keynesians, some of whom were involved intellectually or practically in the economics of developing economies. Keynes, remaining an imperialist as far as India was concerned, nevertheless produced a corpus which has been immensely helpful in understanding developing economies and prescribing policy solutions for them. First, Keynes created the modern macroeconomics discipline and refined the concept of national income, allowing methods of collecting and organising economic and social data enabling assessment of intersectoral impacts. Second, still relevant today is his idea of an International Clearing Union, disciplining countries with excessive balance of payments surpluses or deficits, even though American opposition at Bretton Woods prevented its adoption. Third, although an economist of the short run, Keynes took up issues of vital concern for the development of an underdeveloped economy, departing from his long-held fears about excessive population growth and contributing to policies for stabilising commodity prices. While Keynes remained a Eurocentric imperialist, his dreams for Europe in general and Britain in particular proved relevant for many developing countries today. He supported public investment and state involvement in solving problems of unemployment and industrial restructuring. His analysis of the instability of stock markets and dangers of financialisation remains highly relevant in a world experiencing major stock market crashes in almost every decade since the 1970s.