Tourism is an economic activity that has experienced a strong development all around the world, increasing the welfare of many regions and countries. However, economic principles have only recently been applied to its analysis. This survey deals with the fundamentals of the economics of tourism, presenting a set of characteristics that differentiate the tourism industry from the rest of economic activities. The literature has focused mainly on demand analysis and the assessment of the macroeconomic effects of tourism expansion. Other aspects that are starting to be studied are the cost-benefit analysis of tourism policy, industrial organization and environmental effects. The maximization of social welfare makes it necessary to take into account the value of externalities in investment decisions, and the characteristics of this industry suggest the need for intervention in the system throught taxes and regulation that guarantee the achievement of the social optimum.

Keywords: tourism, cost-benefit, multipliers, demand, environment.