The EPI has been created by experts from Yale and Colombia Universities to look at ten environmental categories for each nation including: environmental health, air quality, water resource management, biodiversity and habitat, forestry, fisheries, agriculture, and climate change.

The United States scored as 61st on the list, plunging twenty-two places from 2008, largely due to failure to deal with greenhouse gas emissions and air pollution problems. Canada also took a big plunge, falling from 12th place to 46th. Canada has come under increasing criticism for its stagnant climate change policies and its tar sands industry.