Judging by the recent actions of companies like Walmart and Samsung, sustainability indexes (aka green supply chain rating systems) are the next big thing in corporate social responsibility. So it isn't all that surprising that a group of 100 retailers and apparel brands are joining together to form an industry-wide Eco Index--a software-based tool that allows companies to track product impacts through a series of questions on labor and environmental efforts.

As expected, "crunchy" brands like REI, Timberland, Columbia, and Patagonia signed up immediately, but the Eco Index has also gained some other supporters, including Target, Nike, and Levi-Strauss. No luxury brands have signed up as of yet, according to the Wall Street Journal. But for the companies involved, the Index has been a long time coming.

In a column for FastCompany.com, Timberland CEO Jeff Swartz explained why the apparel industry needs an Eco Index:

The electronics industry pulled this off; the fashion industry hasn't, at least yet. And so with a lonely label on our products, how are consumers supposed to make an informed, comparative choice between two T-shirts at retail? Sooner or later, our industry is going to get there. Labels will be on all products, and consumers will be able to consume more thoughtfully. And then, responsible profit will be the standard.

Swartz estimates that if the outdoor apparel and shoe industry made an effort, it could have consumer-facing eco-labels on 90% of its products within 18 months. That's largely because of Timberland's efforts in tracking down supply chain information for its own products. Not that Swartz believes this will ultimately help Timberland: "It's a huge opportunity for businesses to lead but there's no smugness in my argument that because we've developed this methodology that it will ultimately be to our advantage," he says. "I don't mind tough scrutiny." Because without scrutiny, consumers can't make informed choices--and companies can't keep track of their competitors' progress.

The industry isn't quite ready to put eco-labels on products quite yet, mainly because the Eco Index brands can't decide on how to publish it. After all, rating the sustainability of a shirt is very different from judging the green qualities of a sneaker.Walmart has been working on its similarly minded sustainability index for the past year, but so far the company hasn't produced any eco-labels either. We don't expect the apparel industry's Eco Index to move much faster.

Ariel Schwartz can be reached on Twitter or by email.