The Maricopa Association of Governments (MAG) MAG was founded in the spirit of cooperation. MAG members believe that by uniting, they can solve common problems, take an active role in long range regional issues, and address concerns that affect communities in the greater Phoenix region. Our Member Agencies include 27 cities and towns, 3 Native nations, Maricopa and Pinal County, and the Arizona Department of Transportation. Our planning area encompasses about 10,600 square miles and represents approximately 5 million people—nearly 70 percent of the state population. Our primary areas of focus include transportation planning, including implementation of Proposition 479, environmental and air quality planning, and human services planning.