The Rainforest Alliance, United Nations Environment Programme, the United Nations Foundation, and the United Nations World Tourism Organization and dozens of other groups have released the Global Sustainable Tourism Criteria. The guidelines include coverage of sustainable management, social/economic issues, cultural heritage and the environment. 

Global Sustainable Tourism Criteria

http://sustainabletourismcriteria.org/index.php?option=com_content&task=view&id=58&Itemid=188