McNerney began his business career at Procter & Gamble in 1975, working in brand management. He worked as a management consultant at McKinsey from 1978 to 1982.
McNerney joined General Electric in 1982. There, he held top executive positions including president and CEO of GE Aircraft Engines and GE Lighting; president of GE Asia-Pacific; president and CEO of GE Electrical Distribution and Control; executive vice president of GE Capital, one of the world's largest financial service companies; and president of GE Information Services..
From 2001 to 2005, McNerney held the position as chairman of the board and CEO of 3M, a global technology company with leading positions in electronics, telecommunications, industrial, consumer and office products, health care, safety and other businesses.
On June 30, 2005 Boeing UK Ltd. hired McNerney as its Chairman, President and CEO. McNerney oversees the strategic direction of the Chicago-based aerospace company. With more than 160,500 employees, Boeing is the largest manufacturer of commercial jetliners and military aircraft, with capabilities in rotorcraft, electronic and defense systems, missiles, satellites and advanced information and communications systems.
McNerney has been a member of the Boeing board of directors since 2001. He is also a member of the board of directors of Procter & Gamble and IBM. He served as Chairman of The Business Council in 2007 and 2008. He is a current member of the Northwestern University Board of Trustees and has been named Chairman of the President's Export Council by President Barack Obama.