The International Joint Commission (IJC) was established by the Boundary Waters Treaty of 1909 to help Canada and the United States prevent and resolve disputes over their shared waters. The IJC’s responsibilities include reporting on progress made under the Great Lakes Water Quality Agreement to restore and maintain the chemical, physical and biological integrity of the Great Lakes and connecting waters. The Great Lakes Science Advisory Board provides advice on scientific matters to the IJC on Great Lakes water quality issues. The board is developing a Great Lakes Participatory Science Guidebook to guide community scientists with best practices and connections to professional science.