For decades, tourism has been one of the fastest-growing industries worldwide. While the number of international tourist arrivals in 1950 was only 25 million, it had risen to 674 million by 2000. In the last year before the COVID-19 pandemic, 2019, there were as many as 1.5 billion international tourist arrivals worldwide. The World Tourism Organization (UN Tourism) estimates that the number for 2024 will be even higher. Domestic tourism has also become more and more important.

As the number of tourists has grown, so has the economic significance of tourism. In 2023, tourism accounted for about ten per cent of global GDP (gross domestic product). About one in ten jobs worldwide is directly related to tourism.

Over the past few decades, the importance of tourist destinations in the Global South has increased continuously. While in 1995 the share of international arrivals in developing countries and emerging economies was only 26 per cent, it was already as much as 38 per cent by 2010. More than half of all Germans have already visited an emerging or developing country.

Tourism can contribute to sustainable development in a variety of sectors.

Economic growth. Tourism generates income and creates training opportunities and easily accessible jobs, as well as sales markets for services and local products.

Infrastructure. For tourism products to meet current expectations, modern infrastructure must be in place. The costs of that infrastructure can be covered through higher revenue from tourism. Better infrastructure improves people's standard of living and often contributes to sustainable, environmentally sound solutions – for example through the development of important transport, energy and other infrastructure assets and through optimised waste and wastewater management.

Environmental protection and nature conservation. Tourism companies and local communities get involved in environmental protection because this will help maintain the basis for tourism over the long term.

Culture. Tourists are interested in local cultures. So tourism can contribute, among other things, towards protecting and reviving the cultural heritage and increasing the value which people attach to it.

Gender equality. The tourism sector offers an opportunity for women in particular to enter the labour market, which often simultaneously gives them a chance to enjoy social and political participation.

Uncontrolled growth of the tourism sector gives rise to a number of risks.

Environment. Uncontrolled growth of the tourism sector puts a strain on natural resources, for example through greatly increased demand for water and energy, increased volumes of waste, and damage to – or even the destruction of – ecosystems.

Human rights. If local people's right to have a say in local affairs is disregarded, or if social standards are not met, tourism can lead to social conflict. In developing countries, a large proportion of workers in the tourism industry have informal jobs with very limited career advancement opportunities. Tourism can also lead to increased sexual exploitation of women and children, and increased child labour.

Economy. Economies that rely one-sidedly on tourism can become economically dependent on that single industry. Seasonal fluctuation of tourist flows can lead to insecure job and income situations.

Crowding-out effect. The construction of tourism infrastructure and the increase of prices in a given region as a result of tourism can crowd out local people from their home areas or local labour and other markets.