After graduating in 1965 from Yale University, Kohler went to work for the Kohler Company which long has been a manufacturer of bathtubs, toilets, other plumbing fixtures, and small engines. He worked as a laborer or technician in every division of the company. In June 1972, he was elected chairman of the board and chief executive officer at the age of 33. Under his leadership, the company more than doubled the size of its engine and generator business and it launched an interiors group that now encompasses five furnishings lines. The National Kitchen and BathHall of Fame inducted Kohler in its founding year of 1989, followed by the National Housing Hall of Fame in 1993. Junior Achievement inducted him into its U.S. Business Hall of Fame in April 2006. Kohler received the "Legend in Leadership Award" from the Chief Executive Leadership Institute of the Yale School of Management later that year. In 2007, Kohler's net worth was estimated at $4.0 billion. In 2009, his net worth was estimated at $1.3 billion and as of June 2016, Forbes has estimated Kohler's net worth at $9.1 billion. Later, in 2019, his net worth was estimated at $8.0 billion.
In April 2015, the company announced Kohler was stepping down as CEO and relinquishing the title to his son, David Kohler, while remaining executive chairman.
Golf
Kohler is an avid fan of professional golf and the Kohler Company owns and operates four courses designed by Pete Dye. At Black Wolf Run there is the River Course and the Meadow Valleys Course. At Whistling Straits there is the Straits Course and the Irish Course. The first course built was Blackwolf Run which is south of the village of Kohler along the Sheboygan River. It hosted the U.S. Women's Open in 1998 and 2012. The second built by Dye was Whistling Straits north of Sheboygan, along Lake Michigan. Whistling Straits hosted the PGA Championship in 2004, 2010 and 2015 and the U.S. Senior Open in 2007. Whistling Straits will host the Ryder Cup in 2020. In 2009, Kohler purchased "one of the sport's most famous buildings", Hamilton Hall, now the Hamilton Grand, a collection of 26 luxury apartments. Kohler owns the Old Course Hotel in St Andrews, Scotland.
Personal life
In 1961, Kohler married Linda Karger, but the couple divorced in the early 1980s. Kohler appeared in the film Open Range, which starred Kevin Costner, and received the role because he was a friend of Costner. Kohler appeared in the newsdocumentary film60 Minutes Sports as himself playing a golf course owner. Kohler owns a successful Morgan breeding facility where he has bred many well known Morgan horses such as HVK Bell Flaire, HVK Courageous Flaire, and HVK Vibrance. He was the owner of the Morgan horseNoble Flaire from 1985 until its death in 2006.