According to the definition and principles of ecotourism established by The International Ecotourism Society (TIES) in 1990, ecotourism is "Responsible travel to natural areas that conserves the environment and improves the well-being of local people." (TIES, 1990). Those who implement and participate in ecotourism activities should follow the following ecotourism principles:

• minimize impact
• build environmental and cultural awareness and respect
• provide positive experiences for both visitors and hosts
• provide financial benefits and empowerment for local people
• raise sensitivity to host countries' political, environmental, and social climate

Ideally, ecotourism should satisfy several criteria, such as:

• conservation of biological diversity and cultural diversity through ecosystem protection
• promotion of sustainable use of biodiversity, by providing jobs to local populations
• sharing of socio-economic benefits with local communities and indigenous people by having their informed consent and participation in the management of ecotourism enterprises
• tourism to unspoiled natural resources, with minimal impact on the environment being a primary concern.
• minimization of tourism's own environmental impact
• affordability and lack of waste in the form of luxury
• local culture, flora and fauna being the main attractions

For many countries, ecotourism is not simply a marginal activity to finance protection of the environment but is a major industry of the national economy. For example, in Costa Rica, Ecuador, Nepal, Kenya, Madagascar, and Antarctica, ecotourism represents a significant portion of the gross domestic product and economic activity.[4][5]

The concept of ecotourism is widely misunderstood, and in practice is often used as a marketing tool to promote tourism which is related to nature. This is an especially frequent malpractice in the realm of Jungle tourism. Critics claim that these greenwashing practices carried out in the name of ecotourism often consist of placing a hotel in a splendid landscape, to the detriment of the ecosystem. According to them, ecotourism must above all sensitize people to the beauty and the fragility of nature. They condemn some operators as greenwashing their operations: using the labels of "green" and "eco-friendly”, while behaving in environmentally irresponsible ways.

Although academics disagree about who can be classified as an ecotourist[6] and there is precious little statistical data, some estimate that more than five million ecotourists - the majority of the ecotourist population - come from the United States, with others from Western Europe, Canada, and Australia.

Currently there are various moves to create national and international ecotourism accreditaion programs[7], although the process is also controversial. National ecotourism certification programs have been put in place in countries such as Costa Rica, Australia, Kenya and Sweden.