Doug Horstman began his career at Williams-Keepers LLC, serving in the tax department for more than seven years. He left the firm to serve as an estimator for a private contractor, which gave him insight into the building construction trade. He returned to public accounting in 1999 and owned an independent accounting practice in Fulton for more than five years before rejoining WK in 2009. Doug provides tax planning and preparation services to individual and business clients.

Currently, Doug serves as the secretary of the South Callaway Fire Protection District. He previously served as treasurer and board member of the Fulton Rotary and Callaway County Special Services. He has also volunteered as a coach for youth baseball, basketball and flag football teams.

Doug graduated from the University of Missouri with a bachelor of science degree in accounting. He is a member of the American Institute of Certified Public Accountants and the Missouri Society of Certified Public Accountants.