Successful cooperation between large manufacturers and their suppliers is a crucial aspect, especially in the automotive industry. Such mutually beneficial cooperation requires at least a certain level of integration and interoperation of the partners’ IT and e-business systems. This chapter looks at two approaches in order to achieve this goal: sector-specific harmonization (in the form of electronic marketplaces) and international, committee-based standardization. This chapter shows that SMEs are facing a severe disadvantage in both cases. This is, however, less pronounced in a formal standards setting, in which capabilities of the individual representatives are more important, at least at the working level.