Political scientists, sociologists, and economists have all sought to analyze the spread of economic and political liberalism across countries in recent decades. This article documents this diffusion of liberal policies and politics and proposes four distinct theories to explain how the prior choices of some countries and international actors affect the subsequent behavior of others: coercion, competition, learning, and emulation. These theories are explored empirically in the symposium articles that follow. The goal of the symposium is to bring quite different and often isolated schools of thought into contact and communication with one another, and to define common metrics by which we can judge the utility of the contending approaches to diffusion across different policy domains.For helpful comments on an earlier draft of this article, the authors wish to thank Barry Eichengreen, Lisa Martin, and John Meyer. Nancy Brune and Alexander Noonan provided excellent research assistance. The authors also wish to acknowledge and thank the Yale Center for International and Area Studies, the UCLA International Institute, and the Weatherhead Center for International Affairs at Harvard University for funding conferences at which this collection of symposium papers were discussed.

Why do powerful states often channel coercive policies through international organizations (IOs)? The article explains this phenomenon by theorizing the political advantages of working through a neutral institution, defined as one with heterogeneous and representative member preferences. The argument centers on the notion of strategic information transmission. IO involvement sends information about the coercer's intentions and the consequences of the coercive policy to foreign leaders and their publics, information that determines the level of international support offered to the coercing state. The logic helps explain why the United Nations Security Council plays a unique role in approving and disapproving the use of force. A case study of the 1990–91 Gulf War shows how these information transmission mechanisms work in practice and that the rationalist information argument provides more traction than a legitimacy-based alternative explanation.For valuable comments on earlier drafts, I would like to thank Charles Glaser, Peter Gourevitch, Lloyd Gruber, Darren Hawkins, Keith Krehbiel, David Lake, Charles Lipson, Daniel Nielson, Kenneth Schultz, Duncan Snidal, Michael Tierney, Daniel Verdier, Erik Voeten, and Joel Westra, as well as participants in the PIPES workshop at the University of Chicago and the conference on Delegation to International Organizations at the University of California, San Diego. I also thank Lisa Martin and two anonymous reviewers for constructive suggestions. I am grateful to Matthew Scherbarth for research assistance and to the Mershon Center at Ohio State University for financial assistance.

How do rising levels of international interconnectedness affect social, economic, and political conditions for women? Research on gender and international relations frequently offers clear propositions but seldom submits them to broad, quantitative testing. This article begins to fill that gap. We advance the hypothesis that, on balance and over time, increasing cross-national exchange and communication lead to improvements in women's status and equality. Economic aspects of globalization can bring new opportunities and resources to women. But equally important, globalization promotes the diffusion of ideas and norms of equality for women. In an analysis of 180 countries from 1975 to 2000, employing cross-sectional–time-series regression techniques, we examine the impact of several measures of globalization on women's levels of life expectancy, literacy, and participation in the economy and parliamentary office. International trade, foreign direct investment, membership in the United Nations (UN) and World Bank, and ratification of the Convention on the Elimination of All Forms of Discrimination Against Women (CEDAW), are associated with improved conditions for women.A grant from the Center for Global Peace and Conflict Studies at the University of California, Irvine, supported this research. The authors are grateful for constructive comments from participants in the faculty research colloquium of the Department of Political Science at Brigham Young University. The authors also received helpful suggestions from their fellow panelists at the 2004 Annual Meetings of the American Political Science Association and from the editor of IO, Lisa Martin, and two anonymous reviewers.

This article studies whether political campaign contributions influence agricultural protection in the United States in the manner suggested by the political economy model of Grossman and Helpman (1994). This is the first attempt to test this model using agricultural data. We test the model using a detailed cross-sectional data set of agricultural protection, subsidies, and PAC contributions in the late 1990s. The model is qualitatively affirmed by the data. We make a novel attempt to solve a puzzle about the model's quantitative implications, also found in recent studies. This solution makes the simple model consistent with the complicated decision-making process in real-world government. The results imply the underpinnings of a political economy equilibrium that will be hard to dislodge.This article has benefited greatly from the insightful comments of the editor and two anonymous referees. We thank Marcelo Olarreaga for access to valuable data on agricultural protection and subsidies. We accept responsibility for any remaining errors. The views expressed are our own and should not be attributed to the World Bank.

Our article analyzes the impact of the European Union (EU) on border conflicts, in particular how integration and association are related to conflict transformation. We approach this issue from a theoretically as well as empirically grounded constructivist perspective. On this basis we propose a stage model of conflict development, based on the degree of securitization and societal reach of conflict communication. We argue that the EU can transform border conflicts and propose a four pathway-model of EU impact. This model comprises forms of EU impact that are, on the one hand, either actor-driven or indirectly caused by the integration process and have, on the other hand, as their main target either particular policies or the wider society in border conflict areas. We then apply this model to a comparative study of border conflicts, thereby analyzing the conflicts in Northern Ireland, Greece-Turkey, Cyprus, Europe's North (EU-Russia) and Israel-Palestine. We finish with a specification of the conditions of positive and negative EU impact.We are grateful to Gesa Bluhm, Olga Demetriou, Katy Hayward, Pertti Joenniemi, Kemal Kirisci, Yosef Lapid, Andrey Makarychev, David Newman, David Officer, Michelle Pace, Sergei Prozorov, Bahar Rumelili, Myria Vassiliadou, Jevgenia Viktorova, Tobias Werron, Antje Wiener, Haim Yacobi, and the reviewers and editors of this journal for their stimulating inputs, criticism, and support in the preparation of this article. Audiences at the Universities of Bielefeld, Hannover, and Osnabrück, Bilkent University (Ankara), the Viessmann Centre at Wilfrid Laurier University (Waterloo, Canada) and the copanelists at the BISA conferences 2002 and 2003, the ISA/CEEISA conference 2003, the ISA Annual Convention 2004, the ECPR Joint Session of Workshops 2004, and the ECPR SGIR Meeting 2004 have helped to shape and refine the arguments presented. We also thank Apostolos Agnantopoulos for his editorial assistance. This article builds on a research project on “The EU and Border Conflicts: The Impact of Integration and Association” (EUBorderConf), funded by a grant from the European Union's Fifth Framework Programme (SERD-2002-00144), with additional funding by the British Academy. See also 〈http://www.euborderconf.bham.ac.uk〉 for further information.

In Jerusalem, Ireland, Kosovo, and Kashmir, indivisible territory underlies much of international conflict. I argue whether or not territory appears indivisible depends on how actors legitimate their claims to territory during negotiations. Although actors choose their legitimations strategically, in order to gain a political advantage at the bargaining table, legitimation strategies have unintended structural consequences: by resonating with some actors and not others, legitimations either build ties between coalitions and allow each side to recognize the legitimacy of each other's claims, or else lock actors into bargaining positions where they are unable to recognize the legitimacy of their opponent's demands. When the latter happens, actors come to negotiations with incompatible claims, constructing the territory as indivisible. I apply this legitimation theory to Ulster, arguing this territory's indivisibility was not inevitable, but a product of actors' legitimation strategies as they battled for support over the issue of Ireland's right to self-rule.For comments on this article, I thank Fiona Adamson, Tim Crawford, Consuelo Cruz, Ron Hassner, Jeff Herbst, Robert Jervis, Robert Keohane, Ron Krebs, Paul MacDonald, Daniel Nexon, John Padgett, Dan Reiter, Jack Snyder, Monica Toft, two anonymous reviewers, as well as participants in a seminar at the John M. Olin Institute at Harvard University. In addition, the John M. Olin Institute, the Belfer Center for Science and International Affairs, the Center for International Studies at Princeton University, and the Center for International Studies at the University of Southern California all provided support for this project.

Over the past forty-five years, bilateral investment treaties (BITs) have become the most important international legal mechanism for the encouragement and governance of foreign direct investment. The proliferation of BITs during the past two decades in particular has been phenomenal. These intergovernmental treaties typically grant extensive rights to foreign investors, including protection of contractual rights and the right to international arbitration in the event of an investment dispute. How can we explain the widespread adoption of BITs? We argue that the spread of BITs is driven by international competition among potential host countries—typically developing countries—for foreign direct investment. We propose a set of hypotheses that derive from such an explanation and develop a set of empirical tests that rely on network measures of economic competition as well as more indirect evidence of competitive pressures on the host to sign BITs. The evidence suggests that potential hosts are more likely to sign BITs when their competitors have done so. We find some evidence that coercion and learning play a role, but less support for cultural explanations based on emulation. Our main finding is that the diffusion of BITs is associated with competitive economic pressures among developing countries to capture a share of foreign investment. We are agnostic at this point about the benefits of this competition for development.For useful comments on earlier drafts of this article, we thank Bill Bernhard, Bear Braumoeller, Frank Dobbin, Robert Franzese, Jeffry Frieden, Geoffrey Garrett, Tom Ginsburg, Jude Hays, Lisa Martin, Bob Pahre, Mark Ramsayer, Steven Ratner, Susan Rose-Ackerman, and John Sides. For research assistance, we thank Elizabeth Burden, Raechel Groom, and Alexander Noonan.

Certain regions of the world experience more conflict than others. Previous analyses have shown that a civil war in one country significantly increases the likelihood that neighboring states will experience conflict. This finding, however, still remains largely unexplained. We argue that population movements are an important mechanism by which conflict spreads across regions. Refugee flows are not only the consequence of political turmoil—the presence of refugees and displaced populations can also increase the risk of subsequent conflict in host and origin countries. Refugees expand rebel social networks and constitute a negative externality of civil war. Although the vast majority of refugees never directly engage in violence, refugee flows may facilitate the transnational spread of arms, combatants, and ideologies conducive to conflict; they alter the ethnic composition of the state; and they can exacerbate economic competition. We conduct an empirical analysis of the link between refugees and civil conflict since the mid-twentieth century, and we find that the presence of refugees from neighboring countries leads to an increased probability of violence, suggesting that refugees are one important source of conflict diffusion.We would like to thank the participants in the “Resources, Governance Structures, and Civil War” Workshop at the European Consortium for Political Research in Uppsala, Sweden, 13–18 April 2004, for early feedback on previous versions of this article. We would also like to thank Anis Bajrektarevic, Lars-Erik Cederman, David Cunningham, Kristian Berg Harpviken, Béla Hovy, Sarah Lischer, Monty Marshall, Erik Melander, Will H. Moore, Magnus Öberg, and Michael Ward for providing us with data and helpful comments, as well as Jan Ketil Rød for permission to reproduce the map from the program ViewConflicts in Figure 1. Finally, we are grateful for the comments and suggestions of the editors of International Organization and the anonymous reviewers. This research was supported by a grant from the National Science Foundation (SES-0351670).

We address the question of how international public goods are financed by analyzing voting in the U.S. Congress on legislation to increase the U.S. contribution to the International Monetary Fund (IMF). We argue that legislators are more likely to vote in favor of an increase (1) the more campaign contributions they obtain from banks that specialize in international lending, and (2) the greater the share of high-skilled “proglobalization” workers in their districts. The first argument supports the inference that a financially strong IMF mitigates the risks of international lending, to the benefit of the lending banks. The second reflects our claim that voters view the IMF as a positive force for global economic integration that—following Stolper-Samuelson reasoning—benefits high-skilled workers. Lastly, we analyze IMF loan decisions and find modest support for the claim that IMF policy reflects the interests of major international banks. Overall, our results suggest that private actors within the United States have individual stakes in funding the IMF.We presented earlier versions of this paper at the 8th Annual International Society for New Institutional Economics Conference (ISNIE), Tucson, Ariz., September–October 2004, and at the Delegation to International Organization Conference, Del Mar, Calif., September 2003. We thank participants for comments. We also thank Michael Hiscox, Mathew McCubbins, J. R. DeShazo, David Lake, Jeffry Frieden, James Vreeland, William R. Clark, Erica Gould, Joseph Joyce, Devesh Kapur, Louis Pauly, Shanker Satyanath, Beth Simmons, and Michael Tierney for suggestions; and Mark Farrales and Molly James for excellent research assistance.

I offer an explanation for the widespread diffusion of neoliberal tax policies in the developed democracies. After accounting for the policy influences of commonly experienced domestic and international forces, I consider several plausible paths of diffusion of neoliberal tax structure. My central argument is that the highly visible 1980s market-conforming tax reform in the United States should be especially important in shaping subsequent tax policies in other polities. There are substantial reasons to believe, however, that domestic political and institutional forces will shape policymaker assessment of the benefits and costs of neoliberal reforms: the strength of right parties and the degree to which the median voter has moved right should condition adoption of neoliberal tax policy; the institutions of national and sector-coordinated capitalism should also slow the enactment of neoliberal tax reforms. I assess these arguments with empirical models of 1981–98 tax rates on capital in sixteen nations. I find that changes in U.S. tax policy influence subsequent reforms in other polities; in the long term, all nations move toward the U.S. neoliberal tax structure. Analysis also shows, however, that the short-term responsiveness to U.S. tax reforms is notably greater where uncoordinated market institutions are dominant. Theory and extensive qualitative and quantitative evidence indicate that pressures to compete for mobile assets, as balanced against the economic and political costs of adoption, anchor the process of diffusion of neoliberal tax policy. There is little evidence for the view that systematic policy learning or social emulation drove tax policy diffusion.Earlier versions of this article were presented at the Center for European Studies and Weatherhead Center for International Affairs, Harvard University; Center for International Studies, UCLA; and Yale University as well as the 2002 Annual Meetings of the American Political Science Association. An earlier version was published as Minda de Gunzburg Center for European Studies, Harvard University, Working Paper #120. I thank Alex Hicks, Rob Franzese, Torben Iversen, Andy Martin, Cathie Jo Martin; participants in the Yale, UCLA, and Harvard conferences, especially Geoffrey Garrett, Helen Milner, Dennis Quinn, and Beth Simmons; and two anonymous referees and the editors of International Organization for helpful comments. I also gratefully acknowledge the contribution of Sven Steinmo that comes by way of our past collaborative work on tax policy.

The constituent influences on congressional voting patterns for trade policy have long been an important field of study. A central theoretical component (explicitly or implicitly) of all these studies is the level of factor mobility that defines which constituent coalitions will form and how they will be affected. Yet the recent literature offers contradictory evidence on the current level of factor mobility. Using an original data set of economic demographics of House districts and the roll call votes of U.S. House members on trade policies from 1963 to 1992, I argue that factor mobility was relatively low in the 1960s and 1970s but was rising. The relative level of factor mobility, then, reached a pivot point in the late 1970s and was subsequently relatively high in the 1980s and 1990s. I check the robustness of these results on the expected strength of the political parties in supplying these policies and the effects of divided government.I would like to thank Oksan Bayulgen, Sam Best, Mark Boyer, Stephen Bronars, Walter Dean Burnham, Virginia Hettinger, Alan Kessler, Peter Kingstone, Tse-Min Lin, Robert Moser, Phil Paolino, Dennis Plane, Howard Reiter, Brian Roberts, Ken Scheve, Lyle Scruggs, Mathieu Turgeon, the editor of IO, and two anonymous reviewers for their helpful comments and suggestions. Any errors that remain are, of course, my own.

We offer a theory explaining how alliances as international security regimes reduce military conflict between member-states through their internal provision of information concerning national military capabilities. Bargaining models of war have shown that a lack of information about relative military capabilities functions as an important cause of war. We argue that alliances provide such information to internal participants, and greater knowledge within the alliance about member-state military capabilities reduces certain informational problems that could potentially lead to war. This internal information effect, however, is a conditional one. We posit that the information provided within the alliance matters most for dyads at or near power parity: the cases where states are most uncertain about who would prevail if a military conflict did emerge. In power preponderant dyads where the outcome of a potential military conflict is relatively certain, the internal information provided by military alliances becomes less important. Our statistical results provide strong support for these theoretical arguments.Our greatest thanks go to Ashley Leeds, who made available an advance copy of the ATOP 3.0 data set. This article also benefited from presentations at the University of Wisconsin and at ISA-South in Columbia, S.C. Finally, we thank Lisa Martin, two anonymous reviewers, Scott Gehlbach, Chuck Gochman, Zaryab Iqbal, George Krause, Pat McDonald, Jon Pevehouse, Bill Reed, Kevin Sweeney, and Harrison Wagner for their detailed comments and/or suggestions.

Most macro cross-national studies in political science that analyze the impact of globalization on domestic policies do not sufficiently consider the methodological consequences of diffusion processes, or “Galton's problem,” as it is often referred to. I argue that globalization is a form of diffusion. Therefore it requires a shift from an exclusively functional analysis, which dominates in almost all established comparative studies in the field, to a diffusional analysis. I assume that globalization leads to a shift in focus on the part of political actors from domestic to international issues. I test this hypothesis by examining social expenditure rates of sixteen highly developed welfare states. The results indicate that globalization has become a highly influential factor since the late 1980s in contrast to the years before. In addition to the actual results presented here, the methodological approach of analyzing globalization as diffusion is relevant to other areas of comparative and international politics and may be a tool in future research.The results of this article are based on a research project, “Environmental Problems as a Global Phenomenon,” which is supported by the German Research Society (DFG; JA 638/7). I wish to thank my research assistants Katrin Daedlow and Bertram Welker for supporting me in data collection and analysis. For constructive comments on different versions of the manuscript, I thank Reinhard Wolf, Kerstin Martens, Susanne Pickel, Kati Kuitto, and above all Elizabeth Zelljadt, two anonymous referees, and the editor of this journal. Most of the revision of this article was written while I visited the Department of Political Science at UCLA. I thank George Tsebelis and James Honaker for comments and advice and Michael Lofchie for his hospitality. I also received invaluable support from Heino von Meyer and Herbert Pfeiffer from the OECD Berlin Centre. Finally I would also like to thank Michael Zürn, who motivated me with his statement that comparative country studies might become obsolete in times of globalization. Without this provocation, this article would not have been written.

Since 1980 almost half of all armed conflicts have been fought between governments and ethnic minority groups over self-determination, yet surprisingly little is known about when and why these conflicts occur. The few studies that do exist focus on the deep injustices and structural conditions that may cause some groups to seek greater autonomy or independence and others not. I argue that ethnic groups are much more strategic than current theories allow. Ethnic groups decide whether to challenge based in part on whether the government has made concessions in the past, and whether the government can be expected to do so again in the future. Data on all ethnic groups for the years 1940 to 2000 reveal that ethnic groups are significantly more likely to seek self-determination if the government has acquiesced to an earlier group of separatists, and if the government is unlikely to encounter additional ethnic challengers in the future. Grievances and opportunity matter, but so does the larger strategic environment in which the government and its ethnic groups operate.I thank Jon Caverley, Rui de Figueiredo Jr., Tanisha Fazal, Zoltan Hajnal, Oliver Kaplan, Jack Snyder, and participants at the Program on International Politics, Economics and Security at the University of Chicago for their very helpful comments and suggestions; Ted Gurr and David Quinn for their detailed information about the CIDCM data set; and Kathleen Cunningham and Idean Salehyan for excellent research assistance. Finally, I wish to thank the National Science Foundation for their support in funding this research.

We examine change in the size of the public sector between 1980 and 1997 across twenty-six Organization for Economic Cooperation and Development (OECD) member nations, with particular attention to diffusion dynamics. General method of moments (GMM) analyses demonstrate imitation of shifts in government employment within the United States and mutual influence among nations that are geographically proximate and that trade extensively. Disaggregated analyses show that downsizing is contagious while upsizing is not: proximate downsizers but not upsizers are imitated, and states act on evidence that downsizing is economically beneficial while ignoring evidence that it is harmful. We argue that these asymmetries in emulation and learning are a product of the dominance of neoliberal and managerialist discourses that legitimate and theorize shrinking the public sector.An earlier version of this article was given at the International Diffusion of Political and Economic Liberalization Conference, Harvard University, October 2003. We thank Frank Dobbin, Geoffrey Garrett, and Beth Simmons for organizing the conference and this symposium; Sarah Babb, Jeeyang Baum, Torben Iversen, Michael Mann, Steve Morgan, Fred Pampel, Deok-Seob Shim, conference participants, and IO's editor and reviewers for their helpful comments; and Thomas Cusack for his generosity in sharing public employment data.

Recent events have raised questions about the extent to which military intervention promotes democracy and the degree to which this depends on the nature of the intervener. We argue that traction on these issues is best obtained by focusing on the policies of the target state that have the greatest implications for the political survival of the intervening state's leader and the kind of governmental institutions in the target state that are most likely to produce them. This perspective generally—although not always—predicts that third-party military intervention in civil wars, other intra- or interstate disputes and wars will lead to little if any improvement, and all too often erosion in the trajectory of democratic development. Three hypotheses on the impact of third-party intervention by democracies, autocracies, and the United Nations are then tested and strongly supported against a counterfactual expectation of what the democratic trajectory would have been in the absence of intervention.We benefited greatly from the wise counsel of Feryal Cherif, Michael Gilligan, Shanker Satyanath, and Alastair Smith, each of whom read or discussed in depth earlier versions of this study. Patrick Regan was also extremely helpful in providing data and guidance in the use of the data on interventions that he has made available. The study was significantly improved by the insightful advice of the anonymous reviewers (we wish we could thank them by name) and by Lisa Martin's able and thoughtful guidance. Authors often complain about referees; we have nothing but praise for the contributions they made. Of course, we alone are responsible for any errors and for all remaining shortcomings in this investigation.

Political decentralization is widely believed to reduce ethnic conflict and secessionism in the world today. Yet decentralization is more successful in reducing conflict and secessionism in some countries than in others. In this article, I explore why this difference occurs. I demonstrate using a statistical analysis of thirty democracies from 1985 to 2000 that decentralization may decrease ethnic conflict and secessionism directly by bringing the government closer to the people and increasing opportunities to participate in government, but that decentralization increases ethnic conflict and secessionism indirectly by encouraging the growth of regional parties. Regional parties increase ethnic conflict and secessionism by reinforcing ethnic and regional identities, producing legislation that favors certain groups over others, and mobilizing groups to engage in ethnic conflict and secessionism.Earlier versions of this article were presented at Harvard University and the Center for the Study of Democratic Politics at Princeton University. The author would like to thank Sandra Alfonso-Leon, James Alt, Micah Altman, Barry Friedman, Shigeo Hirano, Simon Hug, Gary King, Rose Rozaghian, Tulia Falleti, and two anonymous reviewers for their very helpful comments.

International organizations (IOs) have become increasingly pervasive features of the global landscape. While the implications of this development have been studied extensively, relatively little research has examined the factors that prompt states to enter IOs. We argue that democratization is an especially potent impetus to IO membership. Democratizing countries are likely to enter IOs because leaders have difficulty credibly committing to sustain liberal reforms and the consolidation of democracy. Chief executives often have an incentive to solidify their position during democratic transitions by rolling back political liberalization. Entering an IO can help leaders in transitional states credibly commit to carry out democratic reforms, especially if the organization is composed primarily of democratic members. Tests of this hypothesis, based on a new data set of IOs covering the period from 1965 to 2000, confirm that democratization spurs states to join IOs.Earlier versions of this article were presented at the 2004 annual meeting of the American Political Science Association, Chicago; the 2004 annual convention of the International Studies Association, Montreal; and seminars at the State University of New York at Albany and Yale University. For helpful comments and suggestions, we are grateful to participants in these seminars and to Marc Busch, Benjamin Fordham, Yoram Haftel, Lisa Martin, Timothy McKeown, Helen Milner, Ronald Mitchell, Andrew Moravcsik, B. Peter Rosendorff, Bruce Russett, and two anonymous referees.

While increased exposure to the global economy is associated with increased welfare effort in the Organization for Economic Cooperation and Development (OECD), the opposite holds in the developing world. These differences are typically explained with reference to domestic politics. Tradables, unions, and the like in the developing world are assumed to have less power or interests divergent to those in the OECD—interests that militate against social spending. I claim that such arguments can be complemented with a recognition that developed and developing nations have distinct patterns of integration into global markets. While income shocks associated with international markets are quite modest in the OECD, they are profound in developing nations. In the OECD, governments can respond to those shocks by borrowing on capital markets and spending countercyclically on social programs. No such opportunity exists for most governments in the developing world, most of which have limited access to capital markets in tough times, more significant incentives to balance budgets, and as a result cut social spending at the times it is most needed. Thus, while internationally inspired volatility and income shocks seem not to threaten the underpinnings of the welfare state in rich nations, it undercuts the capacity of governments in the developing world to smooth consumption (and particularly consumption by the poor) across the business cycle.The author would like to thank Steph Haggard, Kristin Bakke, Wongi Choe, Tim Jones, and seminar participants at Duke University, Penn State University, Washington University, MIT, and the University of New Mexico for their helpful comments. Nancy Brune, Mark Hallerberg and Rolf Strauch, and Nita Rudra were very generous in providing their capital account, OECD fiscal, and potential labor power data, respectively.

Democracy does not evolve sui generis. The spatial clustering in democracy and transitions suggests that international factors play a prominent role in forging democracies as well as influencing their durability. We argue that democracy often comes about as a result of changes in the relative power of important actors and groups as well as their evaluations of particular institutions, both of which are often influenced by forces outside the country in question. The scope and extent of connections with other democratic countries in a region can strengthen support for democratic reform and help sustain institutions in transitional democracies. Results from a transition model demonstrate that international factors can exert a strong influence on the prospects for transitions to democracy, and the spatial clustering in democracy and transitions cannot adequately be explained by the hypothesized domestic social requisites of individual countries.We are grateful for comments from Brian A'Hearn, Kyle Beardsley, Nathaniel Beck, Scott Gates, Håvard Hegre, David Lektzian, Jon Pevehouse, Dan Reiter, Kenneth Schultz, Heather Smith, Håvard Strand, and Kaare Strøm, the editors, and two anonymous reviewers, as well as the participants at the Conference on the International Diffusion of Democracy and Markets, University of California, Los Angeles, March 2003, and the Conference on the International Diffusion of Political and Economic Liberalization at the Weatherhead Center for International Affairs, Harvard University, Cambridge, Mass., October 2003.