But only a few hotels in the United States are certified as "green" by the U.S. Green Building Council. None of the big hotel chains, cruise lines or tour operators has published a thorough corporate responsibility report, with metrics, goals and timetable for decreasing greenhouse gas emissions.
And while the "eco-travel" category is growing fast, no one can tell you with any certainty just what that means.
What's more, while the industry creates jobs and helps alleviate poverty, critics say that industry workers in the developing world are underpaid, and that most of the tourism dollars generated in poor countries leave anyway. That's because visitors tend to favor western-run hotels, western-owned rental car agencies, and western-made products like Coca-Cola over local businesses.
"The tourism industry lags way, way behind other industries when it comes to corporate social responsibility," said Patricia Barnett, director of Tourism Concern, a British advocacy group.