Lisa L. Martin's groundbreaking new book, Democratic Commitments, challenges this (still dominant) canonical viewpoint by forging strong theoretical and empirical linkages between the realm of domestic legislative institutions and international cooperation. By demonstrating that legislatures in stable democracies have the potential to increase the credibility of states' commitments and thus improve the chance of international cooperation, this book contributes significantly to emerging work on the interaction between the domestic political sphere and international outcomes.

The nature of domestic political arrangements has been shown before to be important for international politics, of course, but a persistent obstacle plaguing the literature is a lack of systematic theorizing as well as overly broad hypotheses. So many things may matter in the domestic realm; the trick is to focus on one element without trivializing it. Martin offers a good example of how to solve this problem by positing the role of the legislature as a crucial explanatory variable in the progress of international cooperation. Legislatures are a key element in the broader debate about the nature of democracy's effects on interstate relations, but they have not received ample study. Martin points to how legislative-executive arrangements reverberate back and forth to the systemic level, and the challenge of credible commitment acts as the fulcrum of her investigation.

The general analytical framework explains how differences in international cooperation may vary with different patterns of domestic legislative structure because of their effect on the credibility of national commitment. Martin evaluates alternative perspectives on executive-legislature relationships, and then she teases out more specific hypotheses from different logics of institutional delegation and how they might play out in the area of international cooperation. Legislative influence, not executive dominance, is her emphasis, against most of the literature and much conventional wisdom. Provocatively, she argues that instead of being pesky interlopers who ruin the chances for serious diplomacy, legislatures contribute to positive and cooperative outcomes by allowing agreements to be reached that are more likely to be implemented.

Martin parses out specific predictions and applications of her general framework in several empirical chapters that range over a variety of areas, but all examine the level of executive discretion in foreign policymaking and the effects of such discretion on the policy outcomes. In the U.S. context, she looks at a series of executive aggreements and treaties over the postwar era, using statistical methods to explore the interaction among the domestic influence of legislatures, decisions regarding ratification processes, and the credibility of U.S. commitments to specific agreements. Other chapters examine economic sanctions and variation in the role of Congress, and foreign aid, particularly food assistance.

The second part of the book applies Martin's line of questioning to Europe and parliamentary governments. Arguing quite rightly that the general outlines of her approach should be applicable in a variety of comparative settings, the author examines how variation in the organization of legislatures across the European Union (EU) had a predictable effect on the particular role member states have played in European integration, particularly decisions over the single market. This research is particularly helpful, given the paucity of systematic empirical work on the role of electoral politics in the path to EU integration.

The book also contributes usefully to practical debates in the EU over democratic accountability, in which democracy and efficiency seem locked in a zero-sum battle. Martin suggests that under some conditions (when legislative involvement makes implementation of agreements more likely) these two ideals can be complementary. Her reading of the EU case suggests that legislative involvement increases when there is a high level of conflict between the executive and the legislature on an issue, but she argues that this may be good in the long term, by making the commitments of states internationally more durable and implementable. This focus on the dynamics of implementation is a real strength of Martin's research, as most scholarship in international relations stresses only the negative effects of legislative involvement in bargaining or ratification processes.

Readers may not be satisfied by some of the solutions to empirical challenges. Much of the analytical story is about indirect, subtle mechanisms of influence. Anticipated reactions, such as the ways in which executives may a priori take into account legislators' preferences, and the dynamics of credibility are two areas critical to political life, but there is unlikely to be much in the way of direct evidence. Martin employs proxy tests and looks for observable, logical consequences in lieu of process-tracing methods. For example, credibility, an inherently intersubjective social phenomenon, is measured by outcomes, that is, commitments are credible when a state does what it says it will do. Despite the thoughtfulness and sophistication with which Martin rises to these challenges, some readers may decide the empirical work demonstrates correlation but not causation. Also, Martin's cases were chosen because they represent interesting substantive areas not probed by other authors, not because they offer the maximum leverage on her critical variables. The mechanics of executive-legislative relations at times become quite complex and contingent in her account, as the specifics of the cases vary dramatically. But these points are dealt with up front by Martin and do not detract from the overall contribution of the book.

As we prepare for the next round of GATT negotiations, we will need to know how domestic politics may play into the future of cooperation. The crucial issue of the timing of the EU's enlargement to the East will undoubtably continue to be entangled with domestic politics as well. The implication of Martin's work for these and a host of other issues demands attention from scholars as well as from policymakers concerned with the future of these international agreements and institutions. Joined (although not necessarily in agreement) with other important works, such as Helen Milner's Interests, Institutions, and Information (1997), the ideas advanced by Martin crystallize one of the promising new directions in the field at the turn of the millenium. Her forceful view that “part of the secret of democratic success lies precisely in its supposed handicap, constant interference in policymaking by legislative actors” (p. 47), is bound to cheer some and provoke many more, both in the scholarly world and in the real one Martin writes about so astutely.