Five volumes of working group assessment reports, which were published which were published on 19 January by the Millennium Ecosystem Assessment (MA) [Millennium Ecosystem Assessment, 2006], synthesize scientific data on the consequences of ecosystem change for human well-being as well as options for responding to those changes.

The MA is an international work program modeled after the Intergovernmental Panel on Climate Change. It was launched by U.N. Secretary-General Kofi Annan in June 2001 and completed in March 2005. More than 1300 authors from 95 countries have participated in preparation of the peer reviewed assessment.