The latest HDR report 2009 tackles the topic of migration and argues that in our highly mobile world, migration is not only inevitable but also an important dimension of human development. Nearly one billion—or one out of seven—people are migrants.

“Migration can be a force for good, contributing significantly to human development,” says United Nations Development Programme (UNDP) Administrator Helen Clark. “But to realize its benefits, there needs to be a supportive policy environment as this Report suggests.”

Indeed, migration can raise a person’s income, health and education prospects. Most importantly, being able to decide where to live is a key element of human freedom, according to the Report, which also argues that large gains in human development can be achieved by lowering barriers and other constraints to movement and by improving policies towards those who move.

However, migration does not always bring benefits. The extent to which people are able to gain from moving depends greatly on the conditions under which they move. Financial outlays can be relatively high, and movement inevitably involves uncertainty and separation from families. The poor are often constrained by a lack of resources, information and barriers in their new host communities and countries. For too many people movement reflects the repercussions of conflict, natural disaster or severe economic hardship. Some women end up in trafficking networks, lose significant freedoms and suffer physical danger.

This is the latest publication in a series of global Human Development Reports, which aim to frame debates on some of the most pressing challenges facing humanity, from climate change to human rights. It is an independent report commissioned by UNDP. Jeni Klugman is the lead author of the 2009 Report.