Reused content are components and parts that are recovered from end-of-life products but are still good enough to be reused in new products, such as building construction and remanufactured electronic products, or as replacement parts for repair, such as in automobiles. Unlike recycled materials, reused content retains its value with minimal processing and therefore tends to be environmentally preferable over recycled materials.

Until recently, reused content has not received the level of attention from policymakers and industry stakeholders that has been given to recycled content. This is partly because ensuring functional compatibility, safety and durability of reused content adds challenges and special recovery is needed. As a consequence, very little data is available. Measuring and tracking reused content is needed to understand the contributions and opportunities of this important method to close material loops in a circular economy.