The current hot spots in ecotourism are the coldest ones - the polar regions, where the effects of global warming are becoming most obvious.
There are cheaper (though not necessarily cheap) options than the once-in-a-lifetime, 15-day cruise including berg walks and penguin sightings offered by the National Geographic Society. But your loved one will get high-level comfort and education going through such an experienced operator.
Other top outfits: Smithsonian Institution and World Wildlife Fund. Find other green tour companies at ecotourism.org.
