This brief article highlights some major contributions made by the United Nations to development thinking and practice from 1945 to 2000. The term 'development' is used here broadly to refer not only to increases in economic growth and per capita income and to structural change, but also to progress in promoting human rights, poverty reduction, employment generation, fairer distribution of the benefits of growth, participation in decision making at different levels, equality of men and women, child development and well-being, and social justice and environmental sustainability.