In Canada and internationally there has been increasing focus on the need to identify the value of goods and services that are naturally provided by biodiversity and healthy ecosystems. We rely upon these "ecosystem services" or "ecological goods and services" (EG&S) to maintain our economy, security, health and well-being. Understanding their value in social and economic terms enables decision-makers to make more fully informed choices supporting healthy environments and communities. The value of most ecosystem services has not historically been included in measures of economic well-being such as GDP (Gross Domestic Product), because they have not been systematically measured. It is now widely recognized that ecosystem services are the fundamental underpinning of our economy.
The Millennium Ecosystem Assessment (MA) is a series of comprehensive reports produced through the United Nations in 2005 that clearly defines and assesses these ecosystem services on a global scale.
Ecosystem services are defined in the MA as comprising four categories:
The MA showed that 60% of the earth's ecosystem services were being degraded and used unsustainably. Degraded ecosystems lose the ability to provide the services that we rely upon, including clean air and water. Environmental scientists and economists have explained that it is necessary to document the value that ecosystem services provide to human society and include that value in economic and environmental decision-making. The outcome should be decisions that secure the ongoing availability of vital ecosystem services through the conservation and sustainable use of earth's natural resources.

Long description for Figure 1.1
Global Biodiversity Outlook 2. CBD Secretariat 2006, Fig. 1.1