The latest figures show the vast majority of the world's 8 billion inhabitants prefer to stay within their nation of birth. But almost 1-in-20 are on the move away from their home.
U.N. leaders used the World Day Against Trafficking in Persons to call for increased prevention against a web of factors.
The number of refugees, internally displaced people and asylum-seekers rose by 2.3 million from 2017. And over the past two decades, the number has doubled.
The Trump administration's broadsides against international cooperation embolden nations with poor human rights records and encourage attacks on journalists, experts said.
Huge security threats loom from the crisis in Yemen to Afghanistan's fighting to the U.S.-China trade war.
The non-binding deal tries to solve some of the polarizing but age-old issues surrounding people crossing borders.
The effort accompanied a similar pact for migration that the U.N. General Assembly also approved this month.
In a world of 7.6 billion people, 44,500 people a day — one person every two seconds — are displaced, the U.N. said.