John M. Dionisio leads AECOM , an $8-billion global provider of professional technical and management support services, as chief executive officer from 2005 to 2011.

John M. Dionisio is a member of Meridiam’s Supervisory Board.

He served as chairman of the company’s board of directors from 2011 to 2014, becoming executive chairman in 2014.

He earned a master of science degree in civil engineering from New York University Tandon School of Engineering (then Polytechnic Institute of New York).