Sustainability (from the latin sustinere - hold up, hold upright; furnish with means of support; bear, undergo, endure) is the ability to continue over a long period of time. In modern usage it generally refers to a state in which the environment, economy, and society will continue to exist over a long period of time. Many definitions emphasize the environmental dimension. This can include addressing key environmental problems, such as climate change and biodiversity loss. The idea of sustainability can guide decisions at the global, national, organizational, and individual levels. A related concept is that of sustainable development, and the terms are often used to mean the same thing. UNESCO distinguishes the two like this: "Sustainability is often thought of as a long-term goal (i.e. a more sustainable world), while sustainable development refers to the many processes and pathways to achieve it."
Details around the economic dimension of sustainability are controversial. Scholars have discussed this under the concept of weak and strong sustainability. For example, there will always be tension between the ideas of "welfare and prosperity for all" and environmental conservation, so trade-offs are necessary. It would be desirable to find ways that separate economic growth from harming the environment. This means using fewer resources per unit of output even while growing the economy. This decoupling reduces the environmental impact of economic growth, such as pollution. Doing this is difficult.
