Humans produce waste extremely easily. From an archaeological point of view, we consider ourselves lucky: waste can be an invaluable source of knowledge about past societies. But for today's society, waste is a bit more problematic. That is, of course, a euphemism. Our plastic soup tastes bittersweet, nuclear waste is hidden in the bowels of the earth, and space debris circles the planet. At the same time, we are starting to recognise that waste can have value when introduced into a circular system to achieve maximum re-use. The best practices are starting to become clear. The circle is becoming complete.