Migrants can bring many benefits to both the countries they move to and the ones they leave behind, according to a major new study.
Migrant workers send their earnings back home across the globe
The International Organization for Migration looked at the costs, benefits and disadvantages of global migration.
It found that common concerns about the negative effects of migration on jobs and welfare costs are often unfounded.
The IOM says there are up to 192 million migrants and many bring a wide range of economic and other benefits.
"We are living in an increasingly globalised world that can no longer depend on domestic labour markets alone.
This is a reality that has to be managed," said Brunson McKinley, head of the IOM.
"If managed properly, migration can bring more benefits than costs."
The IOM cites a British report showing that, between 1999 and 2000, migrants in the UK contributed $4bn (£2.1bn) more in taxes than they received in benefits.
Migrants also make a significant contribution to the economies of their home states, the report says, with returning cash flows sometimes exceeding official development aid.
Rather from taking jobs from local workers, the report says that migrants tend to fill spaces at the poles of the labour market - working both in low-skilled, high-risk jobs and highly skilled, well-paid employment.
Migrants represent 2.9% of the world population
Almost half of them (48.6%) are women
The number of international migrants more than doubled 1970-1990
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"There's very little evidence in many of the Western countries that are receiving migrants that migrants are substituting the local workforce," the report's editor, Irena Omelaniuk, added.
And migrant workers sent back more than $100bn (£55bn) to their countries of origin in 2004. In fact, the report estimates that more than double this figure may also be sent through informal channels.
Morocco, the report says, received $2.87bn (£1.57bn), or 8% of its GDP, from money sent home by migrant workers in 2002 and remittances sent to the Philippines accounted for almost 10% of its GDP.
The report says that, although many skilled workers abandon their home countries seeking higher pay abroad, many can be encouraged to return home bringing acquired skills and experience - a process of "brain gain".
"Trends suggest a greater movement towards circular migration, with substantial benefits to both home and host societies," the report says.
The IOM says that migrants make up less than 3% of the global population and that almost half of all migrants are women.
It says that although the number of migrants has risen, from 82m in 1970 to around 190m people today, some countries - including Asia and Africa - have seen their proportional share of migrants decline.
The most popular destination countries for migrants include the US - which alone is home to more than 20% of the world's migrants - and Russia, home to almost 8% of global migrants.