In this review essay, Wolf-DieterEeberwein comments on the book directed by Josepha Laroche, called La Loyauté dans les relations internationales (Paris, l'Harmattan). This collective book gathers the presentations that occurred during a conference by the International Studies Section of the French Political Science Association (Association Française de Science Politique) the 17 contributions discuss and spot the light on central aspects of the normative foundation of the international system and the judicialisation of international relations.