The human rights group Amnesty International says America's native peoples are still one of the most marginalised and poorest communities in the world, discriminated against and often exposed to grave abuses of their fundamental human rights.
Amnesty published the report to coincide with Columbus or Native American Day, when several countries celebrate the continent's multicultural heritage and mark the arrival in the Americas of Christopher Columbus in 1492.
"Basic rights of indigenous communities, including the right to land and to cultural identity in the use of language, education and the administration of justice are systematically violated," the report says.
"Racism and discrimination entrenched in most societies make indigenous people more vulnerable to human rights violations including torture and ill-treatment, 'disappearance' and unlawful killings," Amnesty argues.
Countries singled out for criticism include:
Amnesty says governments often fail to implement agreements reached with indigenous communities, which can lead to further mistrust and resentment.
Communities downtrodden
"I think Amnesty International reaffirms what many of us have been saying for years," said Rosalina Tuyuc of the National Co-ordination of Guatemalan Widows.
"In all of Latin America, and especially in Guatemala, there have been no advances in recognising or respecting Indian communities."
The report says that in countries such as Argentina, Bolivia, Brazil, Canada and Nicaragua, indigenous people trying to reclaim the lands of their ancestors are facing violent opposition from landowners and companies exploiting natural resources.
The study found that in Colombia indigenous people often find themselves trapped in the crossfire between the army and their paramilitary allies and left-wing rebels.
In Honduras, several native leaders have been killed and no-one has been held responsible for their deaths.
It says that in Saskatoon City in Canada police have been accused of routinely leaving what they consider troublesome members of the indigenous community in isolated areas.
And in Argentina, more than 100 policemen raided the Toba community in the north of the country, beating and racially abusing the residents.
Amnesty is calling on governments to take immediate and concrete action to turn their rhetoric on multiculturalism and indigenous rights into reality.