Upon graduating from college and working summers in course maintenance, Mungeam began employment in golf course construction. He was responsible for the day-to-day project operation at several sites throughout the East, thus learning the construction process in different terrain and soil conditions.
In 1987 Mungeam joined Cornish and Silva. He designs with the philosophy of utilizing the natural characteristics of the site to determine the style of the course. This creates courses with different looks and playing characteristics. A common link between his courses is the incorporation of subtle design features achieved through close supervision and often his personal shaping of the key features.
In 1995 Mungeam became a principal in the firm of Cornish, Silva and Mungeam, Inc. Notable course designs include Shaker Hills & Cyprian Keyes in Massachusetts and The Links at Hiawatha Landing in New York. In 1999 Mungeam oversaw the renovation of Olympia Fields Country Club in Chicago in preparation for the 2003 U.S. Open.