The circular economy represents a powerful new paradigm for materials consumption and solid waste management. Instead of beginning with extraction and ending with waste, the circular economy begins with material already in use, or else material designed for iterative uses, moves through production and consumption, and into waste management, which secures a revived or altered source material, which in turn moves though production and consumption, and so on, over and over again. Achieving significant GHG reductions in this area requires widespread shifts in production and consumption toward what can be expressed succinctly in a familiar refrain: “reduce, reuse, recycle.” There are a number of legal pathways to achieving emissions reductions through materials consumption and solid waste management. Corporate governance as well as R&D of new materials can play a significant role, and significant advances can be made through regulatory interventions.