The CEC held in April 2008 its Fourth North American Symposium on Assessing the Environmental Effects of Trade, which concentrated on the services sector.

The previous three symposia were held in 2000, 2003 and 2005. The first one (2000) focused on the impacts of NAFTA on freshwater, fisheries, forests, hazardous wastes and domestic environmental laws. The 2003 symposium examined the environmental impacts of NAFTA in the energy and agricultural sectors, while the 2005 symposium assessed the environmental impacts of investment and economic growth.

The overall goals of these symposia have been to improve the understanding of the environmental effects of free trade and related economic growth in North America, as well as to identify opportunities for further integration between environmental and trade policies.