International organizations have highlighted the importance of protecting indigenous peoples' environment and lands, the importance of protecting them from exploitation or abuse, and the importance of no contact in order to prevent the spread of modern diseases.

Historic exploitation and abuse at the hands of the majority group have led many governments to give uncontacted people their lands and legal protection. Many Indigenous groups live on national forests or protected grounds, such as the Vale do Javari in Brazil or North Sentinel Island in India.

In 1961, British explorer Richard Mason was killed by an uncontacted Amazonian tribe, the Panará. The Panará lived in relative isolation until 1973 when the government project (Cuiabá-Santarém) road BR-163 was built through their territory. As a result, the tribe was decimated by newly introduced diseases and suffered from the environmental degradation of their land. Of the more than 350 members of the Panará tribe, more than 250 perished in the first twelve months after their first contact with settlers.

Much of the contention over uncontacted peoples has stemmed from governments' desire to extract natural resources. In the 1960s and 1970s, Brazil's federal government attempted to assimilate and integrate native groups living in the Amazon jungle in order to use their lands for farming. Their efforts were met with mixed success and criticism until, in 1987, Brazil created the Department of Isolated Indians inside the Fundação Nacional do Índio (Funai), Brazil's Indian Agency. FUNAI was successful in securing protected lands which have allowed certain groups to remain relatively uncontacted until the present day.

A different outcome occurred in Colombia when the Nukak tribe of Indigenous people was contacted by an evangelical group. The tribe was receptive to trade and eventually moved in order to have closer contact with settlers. This led to an outbreak of respiratory infections, violent clashes with illicit drug traffickers, and the death of hundreds of the Nukak, more than half of the tribe. Eventually, the Colombian government forcibly relocated the tribe to a nearby town where they received food and government support but were reported as living in poverty.

The threats to the Nukak tribe are generally shared by all peoples in isolation, particularly the outside world's desire to exploit their lands. This can include lumbering, ranching and farming, land speculation, oil prospecting and mining, and poaching. For example, then Peruvian President Alan García claimed in 2007 that uncontacted groups were only a "fabrica…

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The Sentinelese people of North Sentinel Island, which lies near South Andaman Island in the Bay of Bengal, reject contact. Attempts to contact them have usually been rebuffed, sometimes with lethal force. Their language is markedly different from other languages of the Andamans, which suggests that they have been isolated for thousands of years. They have been called by experts the most isolated people in the world, and they are likely to remain so.
The Toromona are an uncontacted people living near the upper Madidi River and the Heath Rivers in northwestern Bolivia. The government has created an "exclusive, reserved, and inviolable" portion of the Madidi National Park to protect the Toromona.

Among the Ayoreo people of the Gran Chaco are a small number of uncontacted nomadic hunter-gatherers in the Kaa-Iya del Gran Chaco National Park and Integrated Management Natural Area.

Pacahuaras are believed to be living in voluntary isolation in Pando Department.
Until the 1970s, Brazil attempted unsuccessfully to move anyone on lands that could be commercially cultivated. In 1987, it set up the Department of Isolated Indians inside FUNAI, facilitating the work of Sydney Possuelo and José Carlos Meirelles, and declared the Vale do Javari perpetually sealed off, encompassing an area of 85,444 square kilometres (32,990 sq mi). In 2007, FUNAI reported the presence of 67 uncontacted Indigenous peoples in Brazil, up from 40 in 2005.

The Awá are people living in the eastern Amazon rainforest. There are approximately 350 members, and 100 of them have no contact with the outside world. They are considered highly endangered because of conflicts with logging interests in their territory.

The Kawahiva live in the north of Mato Grosso. They are constantly on the move and have little contact with outsiders. Thus, they are known primarily from physical evidence they have left behind: arrows, baskets, hammocks, and communal houses.

The Korubu live in the lower Vale do Javari in the western Amazon Basin.

The Flecheiros (the "arrow people") are another people living in the Vale do Javari.

Other tribes may include the Uru-Eu-Wau-Wau, and the Himarimã. There may be uncontacted peoples in Uru-Eu-Uaw-Uaw Indigenous Territory and Kampa Indigenous Territory an…

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The Pintupi Nine lived a traditional life in the Gibson Desert of Australia until 1984, having earlier split off from another group of Pintupi people.
The New Guinea Highlands were first visited by Western explorers in the 1930s. The highland valleys were found to be inhabited by over a million people.
Ishi, a member of the Yahi people of Northern California, remained in voluntary isolation from the outside world until 1911 and was acclaimed as the "last wild Indian".
The Matsés made their first permanent contact with the outside world in 1969. Before that date, they were effectively at war with the Peruvian government.