http://www.greencustoms.org/reports/guide/Green_Customs_Guide%20(low).pdf

Multilateral environmental agreements (MEAs) are agreements
between several parties—that is, States or, in some cases, regional economic integration organisations such as the European Union—to pursue specific measures aimed at protecting the environment and conserving natural resources. This type of initiative is often brought about by worldwide concerns about the great and sometimes serious impacts of seemingly harmless human activities on the Earth's fragile environment. In response to these impacts, nations are now questioning the long-term sustainability of such activities in view of the need to ensure a safe future for coming generations.