Definition: One of the best definitions I've found comes from the British Columbia Forest Service - "Sustainability: A state or process that can be maintained indefinitely. The principles of sustainability integrate three closely interlined elements-the environment, the economy and the social system-into a system that can be maintained in a healthy state indefinitely."
Examples:
The concept of sustainable forests or sustained yield comes to us from foresters of the 18th and 19th century in Europe who were concerned about wood depletion.
