The merits, and also the hazards, of competition as an organising principle for society are well traversed in the economic, political science, and legal literature. The phenomenon of regulatory competition – defined most simply as competition between governments for regulatees (p. 3) – is recognised (albeit still debated) as a means by which competition between different systems and/or legal actors can prompt legal reform, with, however, the associated risks of regulatory arbitrage and a “race to the bottom”. This ambitious and wide-ranging study of regulatory competition as it pertains to the EU began life as a doctoral thesis, which garnered its author, Barbara Gabor, a Cappeletti Prize from the European University Institute in 2010. It provides an extensive yet succinct overview of the major issues in the field of regulatory competition, alongside three case studies that trace the parameters of such competition within discrete areas of the internal market. Assessing these legal areas primarily in terms of established economic theory, this book has thoughtful contributions to make to the existing literature on both regulatory competition and the development of the internal market.

In one sense, the notion of regulatory competition should be anathema, or at least redundant, in the context of an internal market, which implies a removal of barriers and concomitant harmonisation of rules across the Member States of the EU. As Gabor's study demonstrates, however, the reality at this stage in the development of the EU is that the so-called internal market continues to present multiple opportunities for divergence and regulatory arbitrage. The author identifies the sources of such variance, from incomplete harmonisation at EU level to uneven implementation by Member States, as well as differing interpretations by national regulatory agencies and courts, and even intra-jurisdictional competition between legal actors within a single Member State. Accordingly, regulatory competition within the EU, largely neglected to date, would appear to be a topic that is ripe for further analysis. This book provides a largely theoretical account of how existing research into the dynamics of regulatory competition can help to explain developments within certain subfields of the internal market, and more generally.

The book begins with an overview of the concept of regulatory competition, which provides, in effect, a literature review of research on this topic to date. The author provides a fairly rapid-fire tour d'horizon of relevant issues, including an explanation of the different forms of competition that can arise, the measurement of the outcome of such competition, the actors that may participate and their individual incentives, as well as the benefits and limitations of such competition. It also introduces the more recent notion of “co-opetition”, under which legal actors may both compete and cooperate (p. 18). Well written and obviously thoroughly researched, this introductory chapter is not for the faint-hearted: it assumes and requires a considerable degree of familiarity with relevant economic concepts, covering a large quantity of material in a fairly abstract manner. The book itself adopts what the author describes as the “broad interpretation” of regulatory competition as systems or institutional competition; this encompasses a wide range of channels of competition including international trade, information flows across borders, and the cross-border mobility of factors of production (p. 50).

The introductory chapter concludes by outlining the author's research agenda, namely to consider the co-opetion model as it applies to the European legal area (p. 52). Having set out “the what”, as the author labels it, the chapter ends with a brief description of “the how” – that is, the format to be adopted by the chapters that follow (pp. 50–54). What is perhaps missing from this introduction is a more nuanced consideration of “the why”. Indeed, this observation might apply to this work more generally: the author has a habit, at the beginning of any new chapter or section, of simply describing briefly the material to follow without linking this to her overall thesis. By consequence, although the work itself contains much of interest, readers may struggle to draw the disparate strands together in a coherent manner, and thus the strength of its overarching arguments is diminished.

The majority of the book comprises case studies examining the operation of regulatory competition in three discrete areas of the internal market: company law, securities law, and competition law. The author, somewhat coyly, explains that these fields were selected “according to several criteria” that are not disclosed, although she notes that, in each instance, the regulated unit is the firm, but the market failures at issue differ (p. 52). Each case study adopts a similar format. The author describes salient characteristics of the legal field concerned, and then considers how the various aspects of the concept of regulatory competition discussed in the introductory chapter would apply. What is perhaps most impressive about these studies is the breadth and depth of the author's familiarity with each of the fields under examination. The book provides an understandable and wide-ranging analysis of the functioning of each of these quite distinct legal fields. Although necessarily somewhat impressionistic in coverage, given the expanse of material to be covered in a short space, the author is effective in identifying and unpicking the most interesting and relevant aspects of regulatory competition that arise in each area.

Each case study then features a “theoretical inquiry” relating to regulatory competition in the field at issue. Both severally and taken together, these abstract, hypothetical, and very general analyses are perhaps the least persuasive aspect of this book. The principal difficulty is that these inquiries add little to the overall analysis of regulatory competition as it applies within the internal market as such. Instead, each theoretical inquiry merely provides the author with an opportunity to apply the existing research of others to hypothetical problems that relate, often quite tangentially, to the specific material considered in the preceding sections. This further compounds the difficulty, noted above, regarding the coherence of the author's arguments: quite simply, given the book's title, it would be more useful to have greater explanation and analysis of what is happening in the internal market than what might happen in hypothetical jurisdictions or situations.

This problem is most acute with respect to the competition law example, where the author notes expressly that the existing legal situation in the EU precludes the scenario she discusses (p. 245). Moreover, even absent this constraint, the author's account ignores important centralising forces within international competition law today, such as the impact of the International Competition Network, the World Trade Organisation, and the so-called Washington Consensus. The company law example features an entirely descriptive law and economics methodology that hardly advances the author's explanation of the dynamics of competition within the field in earlier sections. The securities law inquiry is most convincing, but again relies upon a wholly abstract account that is difficult to relate to the given purpose of exploring regulatory competition within the internal market. Though doubtless competently executed, these hypothetical exercises left this reader at least somewhat nonplussed as to their underlying purposes.

The book's concluding chapter is arguably its most clear, complete, and successful. Perhaps unsurprisingly, the author concludes that different regulatees have diverse preferences (p. 259), so that regulatory competition works rather differently within different legal fields (p. 271). She identifies certain interesting recurring trends across the fields surveyed, including greater reliance upon legal tools that foster cooperation amongst domestic legal actors but leave national competition decentralised, and greater use of economic analysis by legislators and regulators within the EU. The author also addresses, for the first time in a comprehensive manner, the constitutional dimensions of the EU that can affect the operation of regulatory competition within the internal market, including the principles of proportionality and subsidiarity. This latter topic might have been more effectively addressed earlier, in order to flag some of the constitutional pressures and limits that render regulatory competition so complex within the internal market. Nonetheless, the author arrives at sensible, well-reasoned, and relatively concrete conclusions with respect to the functioning of regulatory competition in this context.

In many ways, this book is more concerned with framing ongoing debates within the area of regulatory competition generally than with resolving these with respect to the internal market. As such, it has important contributions to make, although it perhaps raises more questions with respect to regulatory competition within the internal market than it actually answers. The author has a slightly needless tendency to make continuous reference to what the book does not cover, perhaps a hangover from its origins as a doctoral thesis. This serves to highlight the need for greater empirical research in many of these areas, where a great deal of data is obviously available, in order to avoid reliance upon more speculative hypothesising. Gabor's work has highlighted the depth and relevance of this topic, and goes a considerable way towards setting the theoretical parameters of the debate. It is to be hoped that future researchers will take up the gauntlet she throws down, in order to develop the topic of regulatory competition as it pertains to the internal market in a more substantive manner.