It is widely assumed that ecotourism offers sustainable development opportunities in under-developed countries, but little is known about the variables contributing to differential sustainability of multiple ecotourism ventures within a geographic region. This investigation compared differences among rainforest ecotourism sites in Tambopata, Amazonian Peru. These rainforest lodges act as stewards of the surrounding habitat. Different histories and philosophies regarding tourism resulted in varied levels of economic, social and ecological sustainability. This study quantitatively examines the differential sustainability of multiple ecotourism sites in a small geographic region. Tourism in Tambopata has a potential for sustainability of local communities and natural resources. Copyright © 2011 John Wiley & Sons, Ltd.