Management Team



Mike Sheaffer


Since 1987, Mike Sheaffer has served as Hi-Line’s President.  Under his tenure, Hi-Line had grown to serve more than 11,000 customers nationwide. Mike started his career at Hi-Line in 1975, and has held positions in Distribution, Purchasing and Sales before assuming his current role.

As a graduate of Texas Tech University, Mike holds a Bachelor’s degree in Business Administration.

Mike is also Founder and Chairman of the American Pregnancy Association—a national non-profit health organization committed to promoting reproductive and pregnancy wellness through education, research, advocacy and community awareness. Find out more at



Brian Grzymkowski

CFO,  Vice President of Human Resources and Technology

Brian Grzymkowski serves as Hi-Line’s Chief Financial Officer and Vice President of Human Resources and Technology. In this role, he maintains responsibility for the company’s financial, administrative and information technology activities.

Brian has over 30 years of experience in financial operations. Prior to joining Hi-Line in 1992 as CFO,  he held a variety of executive level positions with Unisys Corporation. His last position was Controller of Power and Cable operations over their Dallas, Montreal, and Guadalajara plants.

Brian is a licensed CPA and  an active member of the Texas Society of Certified Public Accountants. He earned his Bachelor of Science in Finance degree from Wayne State University and his Master of Business Administration degree from Golden Gate University.

Outside of Hi-Line, Brian is a co-founder of North Hills Preparatory, one of the first generation charter schools in Texas. North Hills Preparatory is consistently ranked as one of the top high schools in the nation. Brian served as Treasurer of the Board of Trustees for both North Hills Preparatory and Uplift Education, a non-profit charter school management organization operating multiple campuses in the D/FW Metroplex.