Sonja Wiesholzer is a civil engineer who worked for 8 years in civil engineering offices (ILF Beratende Ingenieure, iC Consulenten ZT GmbH) and then moved to the Ministry of Transport (BMVIT/BMK) for 16 years, where she was finally head of department and deputy group leader. During this time, she was, among other things, head of the Tunnel Administrative Authority according to EU Directive 2004/54/EC and was delegated to SCHIG as a supervisory board member and chairwoman of the balance sheet committee. In 2022 she moved to the management of the Executive Board staff for operational excellence and project management at Berliner Verkehrsbetriebe, where she also headed the bus division on an interim basis. As of 1 November 2023, she was appointed Technical Managing Director of Schiene Oberösterreich GmbH.