Although services make up an increasingly larger share of global economies, how to source services is still a rather scarcely investigated field. The p- chasing of services from an international supplier landscape has increased dramatically in the last years, but this practical relevance has not yet echoed in academic research fully. The academic, professional and also political discussions around terms and phenomena such as offshoring are still ch- acterized by a lack of clarity and delimitation of (seemingly) competing terms. Another issue worth highlighting in this field is that despite the g- graphical dimension of this topic, how to best source certain complex service categories, such as for example marketing services, is still particularly under researched. Therefore, the dissertation of Ms Bals was on the one hand particularly concerned with bringing clarity into these terminological issues in the field of international sourcing of services. On the other hand, it focused to further develop the field of complex categories by highlighting specific aspects of sourcing marketing services. These goals have been accomplished exc- lently. Prof. Dr. Christopher Jahns Acknowledgements First and foremost I would like to take the opportunity to state my thanks to the people, who have significantly supported and enabled this thesis.

Dr. Lydia Bals promovierte bei Prof. Dr. Christopher Jahns am SVI-Stiftungslehrstuhl für Einkauf, Logistik und Supply Chain Management der European Business School Schloß Reichartshausen. Sie ist heute als Post-Doc Visiting Scholar an der Columbia Business School, Columbia University (New York, U.S.A.), tätig.

Offshoring: Dimensions and Diffusion of a New Business Concept.- Barriers of Purchasing Involvement in Marketing Service Procurement.- A Theoretical Approach to Problems in Buying Agency Services.