Sustainable tourism is the concept of visiting a place as a tourist and trying to make only a positive impact on the environment, society and economy. Tourism can involve primary transportation to the general location, local transportation, accommodations, entertainment, recreation, nourishment and shopping. It can be related to travel for leisure, business and what is called VFR (visiting friends and relatives). There is now broad consensus that tourism development should be sustainable; however, the question of how to achieve this remains an object of debate.Without travel there is no tourism, so the concept of sustainable tourism is tightly linked to a concept of sustainable mobility. Two relevant considerations are tourism's reliance on fossil fuels and tourism's effect on climate change. 72 percent of tourism's CO2 emissions come from transportation, 24 percent from accommodations, and 4 percent from local activities. Aviation accounts for 55% of those transportation CO2 emissions (or 40% of tourism's total). However, when considering the impact of all greenhouse gas emissions from tourism and that aviation emissions are made at high altitude where their effect on climate is amplified, aviation alone accounts for 75% of tourism's climate impact.