Rich Lesser, global chair at BCG, told the audience at Fortune’s CEO Initiative in Washington, D.C., on Monday that the U.S. pact with China and the setting of coal and methane financing and emissions goals were promising steps forward. “Overall, we should feel like [COP 26] is a good thing, but with huge challenges,” he said.

Government and corporate interests often conflict when it comes to climate change, but the private sector’s turnout at COP26 signaled its commitment to enacting the changes necessary to save the planet, said Lesser, who attended the climate summit in person.

His co-panelist, Banco Santander executive chairman Ana Botin, said she attended COP26 “as an optimist who worries a lot,” but says she left encouraged by business’s participation.

Botin, whose bank was recently ranked No. 4 on Fortune’s Change the World List, challenged the rest of her industry’s leaders to make stronger climate promises. Banco Santander has invested over $11 billion in green energy projects and is also part of the Glasgow Financial Alliance for Net Zero, a group of 450 financial institutions committed to a net zero goal, coal divestment, and climate reporting standards for the industry.

The Santander executive chairman warned that the actions of the finance industry—or any other industry—on its own will not be enough to solve the global climate problem.

“We can not be the only police on climate,” she said, urging governments to set standards and targets for electric vehicle manufacturing, a carbon market, and measures for sustainability and climate impact—as long as they are not too heavy-handed.

While the moral imperative to divert the globe from climate catastrophe may be enough for some business leaders to pursue sustainable practices, others may need a nudge in the form of a business case, Lesser said. Many leaders are betting that corporate climate responsibility will lead to a positive response from current and prospective employees and earn their companies a ‘first-mover’ reputation in consumer and financial markets.

“If you’re looking to build competitive advantage in sustainable value creation, how can you not believe that investing in this tailwind behind you is of interest?” Lesser said. “The flip side [of not addressing climate change] is the risk that someone won’t be your business partner, that you will piss off your employees and be less likely to get top talent, that your investor base will increasingly go to your [shareholder meetings] and question who is on the board.”

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