Negwer has served as president of Ferguson-based Negwer Materials since 1995. The company has been in operation since 1924 and is the premier supplier of interior construction products in central and eastern Missouri and central and southern Illinois.
He serves on numerous boards, including the Lutheran High School Development Board, North County Inc., and the UMB Bank Advisory Board. He served on the executive committee of the Drake Group, an industry association where he served as chairman. Negwer is an active member at Atonement Lutheran Church and served on several civic organizations in Ferguson and North County. Additionally, he has served on various special boards in Ferguson, including the Ferguson Center Committee, Downtown Revitalization Committee and the Ferguson Business District.