In 1909, A.E. McMahon founded a civil engineering firm, working out of a small office in downtown Menasha, Wisconsin, designing the infrastructure that was essential to the growth of communities located in the Fox River valley. With a focus on improving the quality and safety of core municipal infrastructure, Robert McMahon, stepped into his father’s role as the company’s president and gradually grew the business.
Today, President Paul E. Benedict leads the company. Through the efforts of a dedicated staff and innovative management team, the company has expanded in size and services, opened regional offices, and established affiliate companies. The corporate headquarters is currently located in the McMahon Business Park in Neenah, Wisconsin.
Since 1909, the firm has set the pace in an industry that demands its professionals respond to ever-changing trends. Environment, technology, economics, and human behavior all influence how we do what we do. One thing has always remained the same…from the very beginning; McMAHON has been committed to designing for a sustainable future and providing innovative solutions, while placing client’s needs first to attain their satisfaction and trust.

1909
Albert E. McMahon founds A.E. McMahon Engineering Company.

1944
- Company incorporates with the State of Wisconsin as McMahon Engineering Company

1944
Merritt O. Clinton; President 1944-1968

1965
Change of company name to McMahon Associates, Inc.

1968
Arthur Scholl; President 1968-1971

1969
Moves company from downtown Menasha to new office on Midway Road in Menasha

1971
Robert E. McMahon; President 1971-1985

1985
Dennis J. Lamers; President 1985-2018;
current Chairman of the Board

1987
Affiliate Midwest Contract Operations, Inc. (MCO) incorporates serving municipalities with contracted operations and technical support. Becomes independent company in 2013.

1989
Regional office established in Valparaiso, IN

1991
McMahon, Inc. established as company’s Design/Build firm.

1993
Regional office established in Machesney Park, IL

1993
Miller Wagner Coenen partners with McMahon offering additional architectural services and is in incorporated under the name Miller Wagner Coenen/McMahon, Inc. (MWCM).

1995
Corporate Headquarters relocates to McMahon Drive within McMahon Business Park in Neenah WI.

2005
SlaM Architects partners with MWCM

2008
Architecture and Engineering services merge and operate under a single entity – McMAHON

2009
McMAHON celebrates 100th Anniversary

2014
McMAHON celebrates 105th Anniversary

2015
Integrated Public Resources, LLC established as Public Private Partnership (P3) firm.

2018
Paul E. Benedict; President 2018-present

2020
McMahon Associates, Inc. acquires the assets of RW Management Group, Inc., a Wisconsin-based public and emergency management consulting firm.