Prior to serving in the legislature, Shields worked for Quaker Oats Company in St. Joseph for more than 17 years, culminating in the role of logistics specialist. After closure of the St. Joseph Quaker Oats facility, she followed her passion for service and entered Missouri's Alternative Teacher Certification program teaching business education in the St. Joseph School District. In 2006, she was selected by the community board to serve as the president and CEO of the United Way of Greater St. Joseph.

Shields' commitment to community and service shows through her service on several boards and commissions, including board chair for the United Cerebral Palsy, board member for the St. Joseph Chamber of Commerce, board member for the Allied Arts Council and board member of the YMCA of Greater Kansas City. She served as Mid-Buchanan PTA president, on the Commerce Bank CRA Advisory Board, Girl Scouts Leadership Circle and Boy Scouts Troop 216 committee. Her service to Missouri includes serving on the Governor's Complete Counts Census Committee and Missouri's Coordination Board for Early Childhood Education.

Shields is a graduate of the University of Missouri - Columbia and lives in rural Buchanan County with her husband, Charlie. They have two sons.