The concept of sustainable development made its first official appearance in 1980, in the World Conservation Strategy produced by the International Union for the Conservation of Nature. Today, the universally accepted definition of sustainable development comes from the report Our Common Future, published by the World Commission on Environment and Development in 1987: “Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” However, the issue of sustainability only began to be accepted by the international community following the 1992 United Nations Conference on Environment and Development in Rio de Janeiro. In fact, one outcome of the UN conference, which came to be known as the Earth Summit, was Agenda 21, an action plan for achieving sustainable development in the 21st century.