What do a biofuels entrepreneur, a Shanghai university professor, and a Washington D.C.-based software company all have in common? They’re all focused on what’s called the circular economy, an economy that is designed to reuse or recycle its waste, and which continues to grow but is decoupled from gobbling up natural resources.

These three—LanzaTech CEO Jennifer Holmgren, Tongji University Professor Zhu Dajian, and Optoro—are also all winners of last year’s The Circulars, a project created by the World Economic Forum and the Forum of Young Global Leaders. The Circulars gives out awards to business folks, entrepreneurs, academics, and companies that have done exceptional work in developing or calling attention to new processes and ideas for reusing and recycling waste in all its forms.

It might sound wonky, but it’s an important concept. A traditional (some call it linear) economy isn’t designed to reuse or recycle its waste, whether that’s materials, packaging, unused goods, or a chemical biproduct of a process. With a world population ballooning to 9 billion people by 2050, there needs to be much smarter ways to use, and reuse, the planet’s limited resources, like energy, food, water, and raw materials.

For LanzaTech’s Holmgren, her work has been focused on helping her company turn industrial waste gases (like carbon monoxide and carbon dioxide) into more valuable biofuels and biochemicals using microbes. The company, backed by Khosla Ventures and others, has been commercializing its technology in China and Taiwan with big industrial companies.

For Optoro, their software helps retailers and manufacturers resell returned, extra, or unsold items. They have their own e-commerce site, but they also work with the biggies like Amazon and eBay. The company, founded in 2004, has raised funds from Steve Case and Al Gore’s investment firms, as well as Silicon Valley venture capitalists Kleiner Perkins.

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Finally, Professor Zhu Dajian has spent decades researching and writing about the importance of the circular economy and particularly how China needs to adopt a new phase of green growth. You can hear more about his thoughts in one of his talks.

If you know anyone who has been doing inspiring work with the circular economy (or you have!), The Circulars will be handing out seven awards for 2017 to companies, entrepreneurs, investors, governments, and others that have done great work in developing and expanding this important idea. Enter your submission now.

The awards will be handed out at The World Economic Forum’s annual meeting in Davos, Switzerland, in January 2017. The applications close on September 30 (and close on September 15 for the ‘People’s Choice Entrepreneur Award’). Accenture Strategy helps organize the project and Fortune is a media partner for the awards program.