As defined by the World Commission on Environment and Development, a sustainable product "meets the needs of the present without compromising the ability of future generations to meet their own needs".

To be considered sustainable, the materials must be same-cycled into a product of equal value, or up-cycled into a product of higher value; while the process would either have no impact on the environment or improve it.

The term sustainability is often associated with recycling or recycled material. Traditional recycling usually results in some form of degradation to the environment or the materials being recycled. In fact, most recycling is actually down-cycling, as materials are reused in less valuable applications in each cycle.