A clear message coming out of Paris is that, now more than ever, businesses, states and cities are taking the lead on climate.

The conference kicked off with more than 150 heads of state — the largest group of world leaders ever to stand together – urging action to curb the risks of of climate change – the more frequent and severe heat waves, droughts, downpours and rising sea levels that we’re already experiencing.

But I was struck by just how many state representatives, mayors, and business leaders from the U.S. and around the world were here in Paris, all lending their voice to support taking strong action globally to address climate change.

Soon after I arrived, I was honored to participate in a Climate Summit for Local Leaders at Paris City Hall hosted by Mayor Anne Hidalgo of Paris and former New York Mayor Michael Bloomberg. It was the first time local leaders had ever gathered in such numbers during a UN climate change conference.

But their actions on climate started long before Paris. More than 400 cities have signed onto the Compact of Mayors – a global coalition of cities committed to measure and reduce their emissions. Former Mayor Bloomberg explained it this way: “Policies at the local level can make a huge difference. Local leaders are doers.”

Later in the week, I found myself in the company of governors. California Gov. Jerry Brown and former Gov. Arnold Schwarzenegger, Vermont Gov. Peter Shumlin and Washington state Gov. Jay Inslee all attended the conference.

At a private roundtable we hosted, Gov. Inslee talked about the climate impacts his state is facing – from devastating wildfires to lackluster ski seasons. He also spoke about the economic opportunities his state is realizing from clean technologies.

At a public event we hosted, state leaders from California, Illinois and Tennessee described their strategies to cost-effectively implement the Clean Power Plan, a cornerstone of the U.S. commitment to reduce emissions 26-28 percent below 2005 levels in 2025. From encouraging energy efficiency to pursuing cross-state trading, state leaders are focused on policies to spur a cleaner power sector.

Business leaders joined us here as well. At two other C2ES events, CEOs from power companies PG&E and PNM Resources explained how they are working with states on the Clean Power Plan, and executives from Alcoa, Bank of America, Calpine, Google, and NRG talked about ways their companies are innovating and investing to meet climate challenges.

Before we even got to Paris, we had already heard from business leaders that they wanted a strong climate deal. Fourteen major companies joined a statement organized by C2ES calling for an agreement providing clearer long-term direction and transparency and facilitating the global carbon market.

A major highlight of our time in Paris was when our board chairman Ted Roosevelt introduced former Vice President Al Gore at a reception co-hosted by C2ES and the Edison Electric Institute. Mr. Gore, who sounded the alarm on climate change years ago, urged us to keep pressing for action at all levels. And it was fitting to see him in the plenary hall, and hear his efforts recognized by French President Francois Hollande, as the final deal was gaveled through.

As we all head home from Paris, and begin the hard work of meeting new commitments and mobilizing even stronger efforts, states, cities and businesses will be playing an even more critical role. And we at C2ES will keep doing our part to help them do their best.