【Abstract】The talk will focus on the influence of the mental model of transaction cost economics (TCE) on outsourcing research. Outsourcing research has focused on the client′s perspective and has often espoused a "buyer-beware" approach. But, over time markets mature, and clients as well as their suppliers might learn. Based on an meta-analysis of temporal changes in contract types between clients and suppliers and based on a study of antecedent factors that shape successful BPO contracts we assume that the maturity of the IT outsourcing industry and vendor learning are better suited to explain the variance in outcome of outsourcing arrangements than a pure focus on the client side characterstics. We propose to adapt an "expertise-ware" stance as underlying mental model for future outsourcing research. In this talk I will also briefly outline the research agenda / projects of the Chair for Information Systems at TU München.