In her PHD thesis, Tanja dealt with opportunism and the analysis of mutual information asymmetries and thus with a very well-known phenomenon in buyer-supplier-relationships. Since then, she has been dealing with topics related to purchasing, procurement and supply chain management for more than 15 years. As a purchasing expert, she has held various positions, including purchasing of seat components for the automotive industry and as Head of Purchasing for Development Services at the Volkswagen Group headquarters. Since 2022, as Head of Procurement at Volkswagen Poznan Sp. z o.o., she is responsible for both direct and indirect procurement as well as supplier and parts management of all VW Poznan plants. As head of the Regional Sourcing Committee in Poland, she also bundles all the needs of the VW Group's procurement units in the Poland region.