Plant-derived feedstocks are increasingly competitive in plastics production Polymers protect us from the elements, increase the fuel efficiency of cars, protect food from pathogens, help cure disease, and enable renewable-energy technologies. To promote, foster, and enable a sustainable society, we need polymers. Yet polymers can also create serious environmental challenges. Nearly all plastic packaging produced—more than 80 billion kg annually—originates from fossil resources and is disposed of after a relatively short period of use ( 1 , 2 ). An increasing fraction of plastic is recycled or incinerated to recover energy, but most ends up in landfills, littering cities or landscapes, and in the oceans ( 3 ). New recycling concepts ( 4 ), clean incineration, and the development of polymers that can rapidly degrade ( 5 ) will be key to addressing these problems. Shifting from petrochemical feedstocks to renewable resources—making plastics from plants—can also rectify some environmental challenges associated with petrochemical extraction and render plastics production sustainable (see the figure).