This paper analyses the impact of cluster structures on employment development in Germany according to the hypothesis of Porter (1998). It develops a new way of measuring the co-location of suppliers and buyers of intermediate goods in a region based on an input-output approach. The resulting indicator is implemented in a shift-share regression in order to analyse the importance of input-output linkages for the employment development in individual industries. One advantage of this approach is that the results can be compared to earlier studies on localization advantages according to Marshall (1890). The results show that the availability of suppliers and customers in the same region was a major engine for job creation in specific industries in the past. In the period 1998 to 2007 this was particularly observed for service sectors, such as Air Transport or Health and SocialWork but also for some manufacturing industries as well as for Agriculture and Construction. It becomes apparent from the comparison with earlier findings that agglomeration advantages are not realizable within a single industry. Positive effects rather result from the right composition of different industries that have the possibility to establish common production chains. However, for a lot of industries the intensity of inter-industrial interdependence did not play a significant role for their employment development.
