Contrary to some people’s belief ‘overtourism’ is not merely a buzzword or an overused media construct. Overtourism is a real and tangible issue that manifests itself differently in different places. Long before the emergence of the word, UNWTO defined tourism’s carrying capacity as
the maximum number of people that may visit a tourist destination at the same time, without causing destruction of the physical, economic and sociocultural environment and an unacceptable decrease in the quality of visitors’ satisfaction 
There’s no denying that the flourishing of tourism comes with innumerable advantages— Entire economies have been transformed, millions of job opportunities created, investments, export revenues, infrastructure expansion, and myriad new services, activities, restaurants and development projects established in tourist destinations; all have rendered the quality of life for local populations all the more improved.
“Tourism fosters cross-cultural interaction. When organized in a sustainable way and in harmony with the interests of local communities, it reduces prejudice and promotes goodwill. It builds tolerance and understanding,” - Peter De Wilde, The president of the European Travel Commission According to him, economic growth at home can help generate economic opportunity, social cohesion and pride. It is something that governments should enthusiastically embrace. But then again, it could all come at a price if not done in a sustainable manner.
Socio-economic Impacts of Tourism
Locals and host communities often have to bear the negative impact of tourism’s growth. With so many tourists coming and going, tons of waste and garbage is generated from individuals who are not living in the city. And it comes down for the city council to spend generous amounts of resources and valuable man labour to clean it all up. Jaisalmer, a beautiful city in India, experienced huge growth in tourism, but their sewage system has been put under enormous pressure; where leaks threaten to damage the classical sandstone of the city. That accompanied a constant struggle with overcapacity landfills and the inability to keep up with the disposal of trash and garbage generated by inhabitants and tourists alike.
Venice is a city with a declining population, it welcomes millions of visitors each a year, and tens of thousands per day. Picture the impact of so many people on a city so small; everything from traffic, footpaths, bridges, queues, airports, and basic services are all overcrowded and overloaded. Everyone’s favourite spots in the city become traffic jam traps they must avoid, and the city’s infrastructure and amenities are all affected.
Displacement of Residents
Congested streets and overcrowded key vacation spots are not the sole problem of the overtourism phenomenon. More and more city centre flats are being rented out to tourists, and cities are transformed to cater for larger numbers of visitors. Companies for holiday rentals like Airbnb have dominated the already bustling urban cities around the world, increasing the rental market of real estate and displacing residents.
More and more people are starting to protest the reduced affordability of housing and complain of being ousted by the massive influx of tourists. As a general rule, landlords of major tourist destinations make much more money out of tourist’s short-term leases on Airbnb, 'forcing local tenants to pay more, or sometimes even leaving locals in a desperate roller coaster of flat searching because many of them now choose not to extend rental contracts, and instead make more profit from their flats as vacation lets.  With the costs of living always rising, citizens are being forced to move out of the most beautiful cities in the world.
In some parts of the world, the situation is much worse. In Cambodia for e.g., citizens were evicted from fishing villages so resorts can be built on the beaches . And in Venice, the city’s population was cut down to half over the past 30 years, because locals have started moving out and escaping this maddening tourist influx. This phenomenon is known to locals as the “Ven-exodus”.
Other negative consequences of overtourism to the residents of a host country include easy-to-miss things such as cultural clashes and displacement of local retail and shops that used to service residents and are now replaced with expensive outlets that target tourists. As well as, a change in the unique character of neighbourhoods, hometowns and cities.  Oftentimes tourists seek off-the-beaten-track trips and authentic experiences to get a sense of the unique character of one place, only to find that it has died out beneath thousands of crowds and an upsurge of souvenir stores, tour buses, unruly night bars and littered beaches. 
Recently in Tourism Recreation Research Journal, overtourism was investigated as the downside of mass tour ism. The report said: “as over-tourism increases, residents find it difficult to enjoy their place because of traffic jams, degradation of landscapes, congestion and vandalism. In other words, the presence of over tourism can be suspected when local people cannot walk on the street without rubbing shoulders with crowd of tourists.” 
Displacement of Resource Allocation
As tourism continues to grow in countries, it creates more demand on the scarce resources of the nation, more land is required, and consequently, land prices rise. Farmers and other local landowners are encouraged to sell to investors and hotel owners who aim to cater for tourists, resulting in a reduced green belt and reduced food production.
Superficially it may seem like the benefits of tourism profoundly out-weigh the downsides, however, in recent years several writers have expressed reservations about the nature and size of the benefits attributable to tourism and have become increasingly sceptical about the potentialities of tourism as a tool for improving the nation’s economy and as means to maximizing the welfare of the native population.
For example, a study published in the Journal of Sustainable Tourism  revealed that in turkey, when the government fixated on using tourism as a driver of economic development, that ended up causing inequalities between Turkish regions and their social classes. Where the tourist friendly areas took a much larger share of the nation’s capital for infrastructure, further pushing income and class inequality and causing dissent from the parts of the country that were unjustly left underdeveloped.
Another worthy point is that not all the economic benefits of tourism are claimed by the host country, as the tourism industry proves to be an extremely profitable and forever growing industry, most of the tourist’s spending leaks as profit to overseas owners and investors. As the domestic competition gets overrun by international firms and developers, the industry becomes more globalized, and thus leaves very little for local businesses and shops to earn from, little for the city’s council to tax, and not enough to repair the city’s infrastructure. 
Alas, the negative effects of overtourism are not only restricted to the socio-economic impacts. In a study on “Coping with success and managing overcrowding in tourism destinations” , produced by the McKinsey & Company and The World Travel & Tourism Council, the researchers boiled down their results to five major problems associated with tourism overcrowding: First is an overloaded infrastructure, second is the alienation of local residents and degradation of the tourist experience, along with great threats to culture and heritage. All of which were already discussed in this article. Finally, was their last point talking about the damage overtourism causes to nature.
Environmental Impacts of Tourism
When we factor in all the effects of tourism to nature, everything from fuel consumption of the travel industry, livestock emissions to the carbon footprint of hotels and a ccommodations, we find that tourism represents about 8% of the global greenhouse gas emissions. It has become evident that humanity cannot alleviate the effects of climate change without addressing the effects of global tourism on our planet. 
Due to the seasonality of tourism, many cities suffer from a massive flood of people during certain times of the year. This puts high pressure and causes shortages in resources like energy, food, drinking water, and other raw materials that are usually already in short supply in these countries. So local businesses and local authorities are incentivized to expedite extraction efforts to not disappoint tourists and meet their high expectations (proper heating, hot water, pools, etc.). The process of extraction and transport of these resources involves a huge amount of gas emissions, along with other impacts related to their exploitation. That is also amplified by increased construction of recreational facilities. Such development projects take place on beaches and forests to be near beautiful scenery, and causes further damage to the environment that is not easily measured. 
Tourism’s modes of transportation like airplanes, cars and buses, and even recreational vehicles like snowmobiles and jet skis cause annoyance and sometimes even hear loss for the nearby inhabitants. And although city noise is something people can learn to tune out, the same is not true for the wildlife in their natural habitats. The noise pollution that is produced by these vehicles causes great distress to animals and people in the area. 
Littering and Waste
In locations where a lot of tourism activities occur, waste disposal quickly becomes a serious issue, as it damages the environment; in spots like rivers, scenic areas, and roadsides soon become overcome with waste and this can be extremely disruptive of the ecological system functions.
For example, the Caribbean produces approximately 70,000 tons of waste per year, only from cruise ships! Solid waste and littering can seriously endanger the life of marine creatures and ruins the aesthetics of the water and shoreline. In mountain areas like the Himalayas, hikers often leave behind everything from garbage, to camping equipment and oxygen cylinders. Such practices degrade the environment and significantly hurt the local wildlife and cause deterioration to both the flora and fauna of the existing ecosystem. 
It is evident that the victims of overtourism are numerous— Organizations like The World Travel & Tourism Council (WTTC) and UN Climate Change have given this fact great attention. Guidelines had to be discussed for countries and corporations on how to deal with tourism’s effects on the environment. 
There are many negative side effects to the tourism industry that humanity cannot ignore. In the following article, we will cover what possible steps governments and the tourism industry can take to mitigate these effects. In addition to how travelers can be responsible, and how individuals can enjoy and discover the planet without harming it.
-  ‘Overtourism’? – Understanding and Managing Urban Tourism Growth beyond Perceptions | World Tourism Organization [Internet]. E-unwto.org. 2018 [cited 19 March 2019]. Available from: https://www.e-unwto.org/doi/book/10.18111/9789284419999
-  Tourism is a Tool for Tolerance, And We Need More Of That [Internet]. Travel and Tourism Competitiveness Report 2017. 2017 [cited 19 March 2019]. Available from: http://reports.weforum.org/travel-and-tourism-competitiveness-report-2017/tourism-is-a-tool-for-tolerance-and-we-need-more-of-that/
-  COPING WITH SUCCESS MANAGING OVERCROWDING IN TOURISM DESTINATIONS [Internet]. Wttc.org. 2017 [cited 19 March 2019]. Available from: https://www.wttc.org/-/media/files/reports/policy-research/coping-with-success---managing-overcrowding-in-tourism-destinations-2017.pdf
-  Barron K, Kung E, Proserpio D. The Sharing Economy and Housing Affordability: Evidence from Airbnb. SSRN Electronic Journal. 2018.
-  Nachemson A. 'This is my land': Cambodian villagers slam Chinese mega-project [Internet]. Aljazeera.com. 2018 [cited 19 March 2019]. Available from: https://www.aljazeera.com/indepth/features/land-cambodian-villagers-slam-chinese-mega-project-180920150810557.html
-  OverTourism – Responsible Tourism Partnership [Internet]. Responsibletourismpartnership.org. 2019 [cited 19 March 2019]. Available from: https://responsibletourismpartnership.org/overtourism/
-  Overtourism: a growing global problem [Internet]. The Conversation. 2018 [cited 19 March 2019]. Available from: https://theconversation.com/overtourism-a-growing-global-problem-100029
-  Is over-tourism the downside of mass tourism? Tourism Recreation Research. 2018;43(4):415-416.
-  Tosun C, Timothy D, Öztürk Y. Tourism Growth, National Development and Regional Inequality in Turkey. Journal of Sustainable Tourism. 2003;11(2-3):133-161.
-  Theobald W. Global Tourism. 3rd ed. Elsevier Inc; 2005. Available from: http://educatererindia.com/wp-content/uploads/2017/04/Global-Tourism-3rd-ed.pdf?fbclid=IwAR10-l4PW1YEyTwvqvR_Au5a355ucTKwO5l9KD4G8bJnY3UvrBU11tNuO1g#page=107
-  Lenzen M, Sun Y, Faturay F, Ting Y, Geschke A, Malik A. Author Correction: The carbon footprint of global tourism. Nature Climate Change. 2018;8(6):544-544.
-  Sunlu U. ENVIRONMENTAL IMPACTS OF TOURISM [Internet]. Om.ciheam.org. 2003 [cited 19 March 2019]. Available from: http://om.ciheam.org/om/pdf/a57/04001977.pdf?fbclid=IwAR1yqnhc8YSgtWRNA3DFOfuEULO1a2sIPVyuPDsDpt6vZhwD4c0JMtNB-IE
-  UN Climate Change and WTTC Highlight Role of Travel and Tourism in Attaining a Carbon Neutral World by 2050 | UNFCCC [Internet]. Unfccc.int. 2018 [cited 19 March 2019]. Available from: https://unfccc.int/news/un-climate-change-and-wttc-highlight-role-of-travel-and-tourism-in-attaining-a-carbon-neutral-world