The question, of course, is whether even Wal-Mart can make it happen.

“I think it’s going to be a lot of work for a lot of people,” said Jon Johnson, a professor in the Sam M. Walton College of Business at the University of Arkansas, whom the company asked to help create the index, along with Jay Golden at Arizona State University. “But obviously we’re optimistic about the prospects.”

Joe Cavaliere, a senior vice president for customer development at Unilever, a big Wal-Mart supplier, called the indexing idea “a great move forward for the industry.”

Wal-Mart’s sheer size has long enabled it to create ripple effects throughout corporate America whenever it adopts new ways of doing business.

For instance, Len Sauers, the vice president for global sustainability at Procter & Gamble, recalls that a few years ago, when his company and a few others began selling concentrated laundry detergent that uses 50 percent less water  and allows for a smaller container using less plastic  that version was slow to catch on.

In 2007, Wal-Mart decided it would sell only the concentrated detergents.

“Because of Wal-Mart’s leadership in that area, they were able to set a standard for the entire industry,” Mr. Sauers said. “That opened the door to allow it to progress very, very quickly.”

Procter & Gamble said sharing the new sustainability index across the industry was important.

“The last thing a supplier really wants is when you’re doing a separate index for every retailer,” said Tim Marrin, associate director of external relations for Procter & Gamble. “Wal-Mart has invited the Targets, the Costcos, the Tescos of the world,” he said, “to come up with a solution so that there are not 5, 10, 15, 20 different standards that retailers are implementing in their markets.”

But creating a single set of measurements for the entire retailing industry will be complicated. For one thing, some suppliers have concerns about their proprietary information.