It took a few years to gain traction, but Costa Rica's Certification for Sustainable Tourism  has finally firmly rooted among the nation's tourism providers and is now the standard by which to compare hotels (and other tourism entities) according to rational criterion.
The CST seeks to categorize and certify hotels and tour companies according to the degree to which each comply to a model of sustainability. Each entity is graded according to environmental, socio-economic, and other attributes, with 150 variables judged by independent investigators on a level of one to five. They are then awarded one to five "leafs" according to the total score, in much the same way that hotels worldwide are categorized by the well-known "stars" system.
The program goes well beyond merely categorizing hotels etc. by whether they recycle water, etc. While previous attention was given solely to ecological aspects of sustainability, little attention was given to the impact of tourism on the quality of life and sociological and cultural integrity of local communities, and/or the level to which each hotel or tour company honored those aspects. CST rectifies that deficiency. Unscrupulous companies – "greenwashers" – can no longer jump on the ecotourism bandwagon by simply adopting a self-appointed label.
The great thing is that CST certification is now so widely recognized and coveted that hoteliers have been provided a real incentive to improve their practices, with an eye to earning the maximum leafs and therefore a competitive advantage.
Only four hotels in the country have received the maximum five leafs:
Finca Rosa Blanca Coffee Plantation & Inn 
Hotel Si Como No 
Lapa Rios Rainforest Ecolodge 
Villablanca Cloud Forest Hotel Spa & Nature Reserve