There’s an idea for a world without trash.

Items are not just recycled, but created with the intention of making new things out of them after they are used. Imagine if every pair of Levi’s jeans were manufactured with fibers made to be pulled apart and repurposed into a new pair of jeans after the old ones are cast off. The cycle repeats itself endlessly, meaning old jeans become new jeans, rather than being chucked into a landfill.

This is the promise of the “circular economy,” a metaphorical description of a world where nothing ever needs to be discarded because goods are designed with materials that can be constantly remade into something else. It’s important to note that the concept is pretty theoretical at this point. There are companies that are working on making their operations more circular — even big ones like Walmart — but no one yet can claim to have a business free of waste.