The Costanzo obligation: the obligations of national administrative authorities in the case of incompatibility between National law and European law.

This book explores three issues: a) Which European obligations apply to national administrative authorities, with regard to provisions of national law that are incompatible with directly effective provisions of European law? b) Which national constitutional obstacles do they come across by giving effect to these obligations? c) How should the tensions between the European obligations and the national constitutional obstacles be solved?