This report for the UN's World Commission on Environment and Development includes a chapter (Chapter 2, Towards Sustainable Development) which defines sustainability as "satisfying the needs of the present generation without compromising the ability of future generations to meet their own needs"
2012 United Nations conference.
Defines sustainability as "emphasizes a holistic, equitable and far-sighted approach to decision-making at all levels. It emphasizes not just strong economic performance but intragenerational and intergenerational equity. It rests on integration and a balanced consideration of social, economic and environmental goals and objectives in both public and private decision-making”