The United States and Canada now have over 40 years of collaborative history in use of an ecosystem approach to protect and restore the Great Lakes. One of the best examples of this is the cleanup of Great Lakes pollution hot spots called Areas of Concern under the Canada-U.S. Great Lakes Water Quality Agreement. A recently published U.S.-Canada study in the journal Sustainability sheds light on how and why institutional arrangements have changed over time to apply an ecosystem approach in restoring AOCs and to address emerging challenges in each local area.