Warren has dedicated much of his business career to the development and operation of shopping centers and hotels in Minneapolis-St. Paul. In additional to his business career Warren has been active in non-profit work, including nearly 20 years on the board of VocalEssence and more than 25 years as a trustee of Gustavus Adolphus College, both in Minnesota. He sang in the Plymouth Congregational Church choir and VocalEssence Chorus for a number of years. In 1990 Warren was recognized as Business Person of the Year by the Edina (MN) Chamber of Commerce and, in 1999, as a Volunteer of the Year award recipient by MSP Magazine. That same year he was awarded the Greater Gustavus Award by the college. In 2019 he was recognized by Finance and Commerce as an ICON of business in Minnesota. With his wife, Donna, he has enjoyed a winter home in Tucson for the past 15 years.