Sustainability has often been defined as how biological systems can be maintained so that they remain diverse, productive and endure long into the future.
However, the 21st-century concept of sustainability has had to go beyond these narrow parameters and grow in scope to include the development of viable models and technologies for both the human race and planet Earth to survive.
Subsequently, sustainability is a balancing act. As noted in the United Nations 1987 report titled Our Common Future: The World Commission on Environment and Development , sustainable development must meet the needs of the present without compromising the well-being of future generations.