»Public Authorities as Tenderers under EU Public Procurement Law«: Public authorities increasingly compete with private undertakings for public contracts. The thesis evaluates the extent to which the EU public procurement directives provide means to prevent distortions of competition. It focuses on the analysis which competitive advantages constitute state aid and on the legal options of considering that a tender has been affected by state aid. In addition, it examines conflicts of interest arising from close links between contracting authorities and tenderers.