In this collection of papers, leaders in the fields of European and Public International Law outline the origins of these difficult questions and attempt to provide some insights into the relationship between the two legal orders. International law is increasingly becoming part of the legal order of the European Union (EU), a process which this book terms ‘Europeanisation’. It focuses on how Member States' international legal obligations are transformed as a result of their membership of the EU, highlighting that the ‘classic’ relationship between national and international law has now become a triangular one with the EU as an intermediary legal order.Footnote ²

This process has been gaining pace in recent years, and the complexities of the area are deepening as the EU takes on greater responsibility in the fields of international relations and international law. The Treaty of Lisbon envisaged a specific role for international law within the EU:

Though the Lisbon Treaty failed to be ratified, this objective has manifested itself in recent cases before the European Court of Justice (ECJ) which have questioned the hierarchy of the various legal orders. The Kadi decisionFootnote ⁴ held that the European Community (EC) can review the lawfulness of EC measures intended to give effect in the EU to United Nations Security Council Resolutions, and this involved no challenge to the primacy of that resolution in international law. The ECJ affirmed as a matter of principle that the review of the validity of any EC measure in the light of fundamental rights must be considered to be the expression of a constitutional guarantee stemming from the EC Treaty as an autonomous legal system which may not be prejudiced by an international agreement.

Although this important judgment was delivered after the publication of this book, it includes a full and detailed analysis of earlier stages of the caseFootnote ⁵ demonstrating the prescience of the editors and authors as to the issues of the moment. Similarly the book contains chapters on the interplay between Community Fundamental Rights and the European Convention on Human Rights,Footnote ⁶ the ever-more blurred distinction between exclusive and shared competences and mixed agreements and the difficulties of implementing WTO law in the EU, as recently demonstrated in the FIAMM caseFootnote ⁷, and customary international law in the EU.Footnote ⁸

As well as highlighting these contemporary issues, this book provides the reader with a comprehensive study of how international law, once implemented in EU law, becomes part of the EU legal order, governed by its own rules such as the principles of direct effect and supremacy. Often referred to as a sui generis entity,Footnote ⁹ or as Jacques Delors once stated, an ‘objet politique non identifié’, the EU does not fit the classical monist/dualist divide, but obeys a different model particular to itself. In this respect, some readers may feel the book insufficiently questions the premise of the title; that EU law is to a certain extent also being ‘internationalised’. It discusses in detail how international law is shaping EU law, but does not develop the notion that EU law is therefore increasingly a product of international law and the impact this has on the EU legislature. Chapter 11 also views the relationship from the reverse perspective, assessing to what extent EU legislation and policies are in fact influencing international law. An example of this is the European Court of Human Rights' willingness to look at ECJ decisions on fundamental rights in deciding their own cases, which is lightly touched upon in Chapter 7. However, the book would perhaps have benefited from balancing these two perspectives more carefully, rather than being dedicated predominantly to one view with only one contribution concerning the reverse.

The book also covers the relationship between the EU and national law. As stated in Chapter 2, this is a dual relationship; the EU interacts not only with the legal system of a Member State (a vertical perspective) but also in its relationship with other Member States (a horizontal perspective), acknowledging the need for and enhanced status of comparative law.Footnote ¹⁰ In this respect, the study of the impact of EU law in some Member States (Austria, Hungary) and third States (Liechtenstein, Switzerland, USA) is valuable, although one may perhaps question the choice of the states studied. Interestingly, the articles on the Member States intended to illustrate the relationship between international, EU and national law actually demonstrate some differences in approach to this relationship, depending on the State. For example, Chapter 8 states that although the international agreements the EC concludes are considered part of the Community legal system, such agreements are not to be considered Community law, but rather international law.Footnote ¹¹ In contrast, the Hungarian article notes that in Hungary, international agreements concluded by the EC are thought of as Community law rather than international agreementsFootnote ¹².

This review has sought to analyse the book from the perspective of an international or comparative lawyer, for whom it constitutes essential reading clearly illustrating the development and convergence of the two subjects and a useful introduction to the impact of EU law on international law and the obligations of Member States. Despite the criticisms made above, this is a timely and important contribution to this ever-changing field of debate, and constitutes one of the only books concentrating on the relationship between Public International Law and European law.Footnote ¹³ It will also be a key volume for academics working in the field of ‘Europeanisation’, as it may now be known.