The CEO Action for Diversity and Inclusion will focus on three main areas: Creating a safe workplace environment for dialog, mitigating unconscious bias, and sharing best – and worst – practices. But the CEO Pledge makes both the business and moral case for diversity:

The persistent inequities across our country underscore our urgent, national need to address and alleviate racial, ethnic and other tensions and to promote diversity within our communities. As leaders of some of America’s largest corporations, we manage thousands of employees and play a critical role in ensuring that inclusion is core to our workplace culture and that our businesses are representative of the communities we serve. Moreover, we know that diversity is good for the economy; it improves corporate performance, drives growth and enhances employee engagement.

The idea was first proposed by Tim Ryan, the U.S. chairman of PwC, who created a company-wide series of dialogs last July, after a series of police-involved shootings left the nation reeling. While the conversations, focused on race, were often painful, the results were transformational for employees and leadership alike. Ryan took the unusual step of announcing his plan for a broader movement in this story for Fortune last February when the idea was still very much in its early stage:

After the success of the July events, followed by the firm’s commitment to continue the work in local markets, Ryan began making calls—lots of them. His dream was to get all the Fortune 500 CEOs together to change the world. Soon a short list of his counterparts at major companies emerged, including at competitor firms, who had similar ambitions and were open to working together on the thornier issues of race. So far, two dozen giant enterprises have agreed to work with him.

Julie Sweet, the CEO of Accenture North America, was an early supporter of the idea. “We started with a group of CEOs who believe strongly that diversity is important to our country and our businesses, and that we had a better chance of making progress together,” she told Fortune in an e-mail. David S. Taylor, CEO of P&G, was also an early supporter. “We started holding dialogue sessions last year at P&G, and it was very eye opening because we were able to hear from people who were being very honest about how they felt,” he said in a statement.

But to get the initiative ready for launch involved no small measure of top line hustle, CEO to CEO. The consulting and audit firms, for example, were responsible for pitching their client firms.

“We all had to work hard,” Ryan said when I sat down with him for a progress report last month. Walmart had just signed on after a personal appeal on a site visit, he told me. And, he’d landed another big supporter just a few minutes earlier. “I just met Randall for the first time,” he said, referring to Randall Stephenson, AT&T’s CEO. The two men had been back-to-back speakers at the Great Place to Work for All conference in Chicago. “The ask hadn’t gotten to his desk yet, but this is a thing I know he really cares about. He gave me his pledge on the spot.”

Though PwC has led the way in money and person-power for the alliance, Ryan credits the early input from like-minded people for shaping the program from the start. Ron Parker, CEO of The Executive Leadership Council, an organization of black executives dedicated to corporate diversity and inclusion, helped craft the group’s ultimate message. “We went through a whole bunch of iterations,” said Ryan. “We had to keep asking ourselves, ‘what we are really trying to accomplish?’ It started out just about race, but by January, we knew we needed to include so much more.”

And not everyone is starting from the same point. “From the very beginning, we were thoughtful in how we approached the commitment to attract a broad group of companies, beyond those that already have significant programs place,” says Sweet. “Our focus is not on metrics, but creating a forum that will help many companies benefit from sharing their experiences, both successes and failures.”

The website is populating now, so check back often. There is a summit planned for this fall to help signatory companies build on what they’ve learned, but it’s not just about them. PwC is one of many companies that is planning on making their bias mitigation or similar training available for public benefit.

For now, Ryan is excited about what the business world can learn when it collaborates. “We’re now into thousands of businesses across the country working at a scale we’ve never seen,” he said.