Environmental, economic and social well-being for today and tomorrow
Sustainable development has been defined in many ways, but the most frequently quoted definition is from Our Common Future. also known as the Brundtland Report: 
"Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs. It contains within it two key concepts:
the concept of needs , in particular the essential needs of the world's poor, to which overriding priority should be given; and
the idea of limitations imposed by the state of technology and social organization on the environment's ability to meet present and future needs."
All definitions of sustainable development require that we see the world as a system—a system that connects space; and a system that connects time.
When you think of the world as a system over space, you grow to understand that air pollution from North America affects air quality in Asia, and that pesticides sprayed in Argentina could harm fish stocks off the coast of Australia.
And when you think of the world as a system over time, you start to realize that the decisions our grandparents made about how to farm the land continue to affect agricultural practice today; and the economic policies we endorse today will have an impact on urban poverty when our children are adults.
We also understand that quality of life is a system, too. It's good to be physically healthy, but what if you are poor and don't have access to education? It's good to have a secure income, but what if the air in your part of the world is unclean? And
it's good to have freedom of religious expression, but what if you can't feed your family?
The concept of sustainable development is rooted in this sort of systems thinking. It helps us understand ourselves and our world. The problems we face are complex and serious—and we can't address them in the same way we created them. But we can address them.
It's that basic optimism that motivates IISD's staff, associates and board to innovate for a healthy and meaningful future for this planet and its inhabitants.
This conference was held in Ottawa, Ontario, October 18-19, 2007 to reflect on the past twenty years of sustainable development in Canada since the publication of the Brundtland report in 1987. The presentations are now available as well as information from the conference.
Looks at the most important successes and failures in SD in the decade following the 1992 Rio Earth Summit. Published in 2002 to coincide with the World Summit on Sustainable Development in Johannesburg.
IISD's Reporting Services is building a sustainable development knowledge base in preparation for Rio+20. Click here to follow international policy developments on sustainability .
Silent Spring was published in 1962. The book's release was considered by many to be a turning point in our understanding of the interconnections among the environment, the economy and social well-being. Since then, many milestones have marked the journey toward sustainable development. The Sustainable Development Timeline captures some of the key events. The original version was published in 1998 with the support of the International Development Research Centre.
 1. World Commission on Environment and Development (WCED). Our common future. Oxford: Oxford University Press, 1987 p. 43.