The number of tourists visiting natural areas has increased dramatically in the past several areas. Specialist tours – birding safaris, camel treks, guided nature walks and so on – are on the rise. However, tourism is a double-edged activity. It has the potential to contribute in a positive manner to socio-economic achievements but, at the same time, its fast and sometimes uncontrolled growth can be the major cause of degradation of the environment and loss of local identity and traditional cultures. Negative impacts from tourism occur when the level of visitor use is greater than the environment's ability to cope with this use within the acceptable limits of change. Uncontrolled conventional tourism poses potential threats to many natural areas around the world. Overcrowding and indiscriminate concretization, not only creates ugly blots on the landscape, but also gives rise to problems of sewage and solid waste disposal. It can put enormous pressure on an area and lead to impacts such as soil erosion, increased pollution, discharges into the sea, natural habitat loss, increased pressure on endangered species and heightened vulnerability to forest fires. It often puts a strain on water resources, and it can force local populations to compete for the use of critical resources. Thus, tourism policies have to be integrated with environmental policies.

Environmentally responsible tourism is a new concept. Its formal enunciation emanates from the 1989 Hague Declaration on Tourism, which advocates rational management of tourism so that it contributes to the protection and preservation of the natural and cultural environment. The Brazil Earth Summit, 1992 aptly discussed the issue of 'Sustainable tourism' i.e. tourism without harm to the environment, within the context of overall sustainable development.

Ecotourism is defined as "responsible travel to natural areas and ecologically fragile areas, so that there is a minimum impact on the environment and improves the well-being of local people." Ecotourism is about uniting conservation, communities, and sustainable travel. This means that those who implement, participate in and market ecotourism activities should adopt the following ecotourism principles:

1. Minimize physical, social, behavioral and psychological impacts.

2. Provide positive experiences for both visitors and hosts.

3. Provide financial benefits for conservation as well as local people.

4. Build environmental and cultural awareness and respect.

5. Design, construct and operate low-impact facilities.

6. Recognize the rights and belief of indigenous people.

For a controlled tourism, carrying capacity of eco-fragile areas have to be kept in mind. "Tourism Carrying Capacity" is defined by the World Tourism Organisation as "The maximum number of people that may visit a tourist destination at the same time, without causing destruction of the physical, economic, socio-cultural environment and an unacceptable decrease in the quality of visitors' satisfaction". By 'carrying capacity', is meant the load of people that a particular area can take. Therefore, in every case it is necessary, to do a detailed study of the carrying capacity of any tourist location, be it a hill-station or a beach resort or a wildlife sanctuary. The carrying capacity would further determine the optimum number of people required to sustain it both economically as well as environmentally. It would be a good idea if the tourism industry itself undertakes such carrying capacity studies in its own enlightened self-interest.

Ecotourism is making the entire travel industry more sensitive to the environment. It incorporates both a strong commitment to nature and a sense of social responsibility. Ecotourism as a logical component of sustainable development, requires a multi-disciplinary approach, careful planning (both physical and managerial) and strict guidelines and regulations that will guarantee sustainable operation.  Only through intersectoral involvement will eco-tourism truly achieve its goal. Governments, the private enterprise, local communities and nongovernmental communities all have an important role to play.

Tourism can be a powerful tool favoring environmental conservation particularly through enhancement of public awareness of environmentally sensitive areas and their resources and the stimulation of action and mobilization of support to prevent the erosion of such environments.