Research done by researcher involved with the IMP approach has shown clearly that companies that manage to build effective long-term relationships with its suppliers in many cases can achieve higher efficiency, higher quality and a higher rate of innovation than companies who rely solely on competitive, arms-length transactions. Private companies can freely use high-intensity relationships (Araujo et. al., 1999) when this is suitable and thus achieve these advantages.However, for public purchasers, the possibility to build long-term supplier relationships has typically been limited by European and national public purchasing directives. The EU has recently initiated a comprehensive reform of the directives, with among other things, a particular focus on public-private collaboration and innovation. The traditional, arm's length approach towards suppliers seems to give some way to more dialogue and interaction based purchasing approaches.This article will first summarize research that has been critical of the previous public purchasing directives and that has aimed to explain how and why these directives have been limiting. Next, we then discuss the upcoming changes in the EU public purchasing directives in the light of this criticism and we develop some conjectures about the effects we think they might have. Finally, we propose some important areas for future research in this area.