Simmons took over in 2007 and oversaw a corporate rebrand in 2010 from the Royal Canadian Golf Association to Golf Canada. He also helped to secure and renew title sponsorships of the RBC Canadian Open and CP Women's Open.
''It has been an honor to represent and lead Golf Canada for the past 10 years, but I felt the time was right to seek out new challenges,'' Simmons said in a statement Wednesday.