How can you tell if an “eco” tourism business is truly green? It’s a question that travelers are asking more and more, and—as sustainability becomes a selling point and greenwashers flood the marketplace—it’s harder to answer than ever.

Attempts at ecotourism certification have been fractionalized and controversial, which means a traveler’s best hope of peeling away the green veneer, at present, is to undergo the tedious chore of calling each operator and asking a lot of pointed questions.

But not for long.

One of the highlights of last week’s Ecotourism and Sustainable Tourism Conference was a workshop on the Global Sustainable Tourism Criteria, an effort by 32 international organizations working to standardize sustainability principles throughout the industry.

GSTC features major players from every sector of the travel world, from mainstream lodging organizations and travel publications to well-vetted ecotravel groups. Getting all these folks to collaborate was no small feat.

“We will certify the certifiers," Ronald Sanabria, the passionate, charismatic, sustainable-tourism director for Rainforest Alliance, told workshop participants at the Fairmont Hotel Vancouver. Sanabria was a driving force behind the initiative, along with representatives from the United Nations Environment Programme, the United Nations Foundation, and the United Nations World Tourism Organization.

When the results are unveiled in January, the many scattered agencies that issue green stamps of approval can finally base their judgments on universal standards.

You can preview the criteria here.