- The Board of the Millennium Ecosystem Assessment represents the users and audiences for the findings of the MA and helps to ensure that the MA will produce information and build capacity needed by the users of the Assessment at local, national, regional, and global scales.
- The Assessment Panel directed the scientific process of the assessment, and is comprised of the co-chairs of each working group, three at-large members, and the Panel Co-Chairs. The members were appointed by the Board, and as the panel directed the assessment itself, its members were selected to reflect the desire for diversity in the MA: balance between North/South, natural and social sciences, and gender.
- The MA Secretariat was composed of staff from six different institutions and provides core administrative, logistical, and technical support to the working groups and committees that are involved in the assessment.
The concept of the Millennium Ecosystem Assessment was developed in 1998 and 1999 by the members of an Exploratory Steering Committee assembled at the invitation of World Resources Institute, United Nations Environment Programme, United Nations Development Programme, and the World Bank. The Exploratory Steering Committee ended its work when the formal MA Board was appointed in 2000.