World leaders and thousands of others are gathering in San Francisco for the Global Climate Action Summit, the biggest climate conference ever held on U.S. soil.

E2 is here in force too, with members, chapter directors and staff from every region of the country coming to town for the Sept. 12–14 summit.

“I am attending because I care about the future of this planet and want to ensure my kids and future generations have clean air and clean water,” said Greg Smith, founder and president of Ohio-based Energy Optimizers, an energy efficiency company that makes schools and other buildings more efficient. “I believe the clean energy economy, businesses and professionals are the key to both growing the economy and ensuring clean air and water for future generations.”

Like Greg, world leaders (unless they happen to be in a state of denial) know we can address climate change and protect our environment while also creating jobs and driving economic growth in clean energy and other sectors.

The opportunities are huge. In America alone, more than 3.2 million people work in clean energy — renewables, energy efficiency and other sectors. That’s more than work in agriculture, in real estate, in investment banking in this country. And it’s three times the number of Americans who work in fossil fuels.

But world leaders converging on San Francisco also know they need businesses to make real change happen at scale. That includes major international companies but — just as importantly — entrepreneurs like Greg and others.

“Scaling solutions is a priority — the private sector must continue to lead the transition to a clean and regenerative economy,” said E2 member Archie Kasnet, founder and president of Massachusetts-based Regenerate LLC, an environmentally focused holding company. “The climate summit is welcoming international leaders from NGOs, business, government and academia focused on creating jobs and growing the economy towards a thriving future.”

That’s what makes the Global Climate Summit so important right now. It’s bringing together business, government, investors and environmental leaders together to develop solutions to the most serious problem facing our world and our children — climate change.

And a time when leadership on climate and clean energy is missing in Washington, DC., that type of collaboration is more important than ever.

Note: this blog post also appeared on Medium.