The concept of sustainable development is related to environmentalism but has evolved since its introduction in the 1980s. The most widely held definition was published by the United Nation's World Commission on Environment and Development (also known as the Brundtland Commission) in 1987. The General Assembly found sustainable development to be that type of development that meets the "needs of the present without compromising the ability of future generations to meet their own needs."
The Commission further defined two key concepts of sustainable development: (1) needs, specifically the essential needs of those living in poverty; and (2) limitations, specifically those imposed by technology and social structures on the environment's ability to meet present and future needs. The approach is thus one that aims to meet human needs, including those of future generations, while also protecting the environment.
In meeting that basic needs of all people, sustainable development's ultimate goal includes the elimination or mitigation of poverty, unemployment, and other social inequities. As a result, sustainable development often focuses on people who live in developing nations. Three aspects of development are integrated in an attempt to accomplish this: environmental sustainability, socio political sustainability, and economic sustainability.
Environmental sustainability aims to preserve the earth and its resources for future generations. In attempting to do this, people should only use as much of a resource as can be replenished naturally. Using resources at a higher rate may deplete or exhaust them in the future, leading to an unsustainable situation in which the planet may no longer be able to support human life.
In socio political sustainability, democracy is promoted in an effort to meet basic human needs by providing basic human rights. These needs include food, shelter, education, health care, and a fair distribution of income. Through empowerment, social development strives to empower people to meet their own needs and improve their own lives.
In economic sustainability, the availability of work is increased, thereby empowering people to support themselves. Industries such as sustainable agriculture are often promoted in this approach. Socio political and economic sustainability are interrelated and complementary; only with the success of both can sustainable development be fully realized.
Green development is often confused with sustainable development. The two concepts are related but distinct. Green development focuses more on environmental sustainability without promoting economic or socio political development at the same time. For this reason, proponents of sustainable development sometimes argue that green development cannot be attained in developing nations, as the countries will lack the economic and socio political conditions necessary to support its implementation and costs.