Peacekeeping is perhaps the international community's most important tool for maintaining peace in the aftermath of war. Its practice has evolved significantly in the past ten or fifteen years as it has been used increasingly in civil wars. However, traditional peacekeeping between states is not well understood. Its operation is undertheorized and its effects undertested. This article explores the causal mechanisms through which peacekeepers keep peace and examines its empirical effects after interstate wars. To take the endogeneity of peacekeeping into account, it also examines where peacekeepers tend to be deployed. Duration analysis shows that, all else equal, peacekeeping significantly increases the chances that peace will last. Peacekeepers can help adversaries to maintain peace by making surprise attack more difficult, by reducing uncertainty about enemy intentions, and by preventing and controlling accidents and incidents that can spiral back to war.

Why has the rate of expansion of postcommunist state administrations varied so widely among countries that are at comparable stages of economic transition, have similar formal institutions, and have been equally exposed to the dynamics of EU integration? Based on a close comparison of Poland, the Czech Republic, and Slovakia, the author argues that the critical factor in postcommunist state building is the robustness of party competition. The legacy of communism creates strong pressures for patronage politics, which swells the administration, but it is party competition that determines whether the predisposition to patronage politics in fact becomes the practice of patronage politics. The number of state administrative personnel has expanded significantly more in countries where party system development has stalled, and party competition has failed to constrain the party(ies) of government.

This article examines obstacles to economic reform in Ukraine's transition to a market-based economy. Existing explanations for failures of reform in postcommunist states privilege societal actors, as in the case of Przeworski's J-curve, or state actors acting in a private, rent-seeking capacity, as in Hellman's partial reform equilibrium. Other explanations focus on weak state capacity. However, there is evidence to suggest that some groups of individuals who stall or halt market reforms may do so in their capacity as state actors. Their resistance to reform may be sub rosa: state actors may comply with formal institutional requirements of reform even as they seek to preserve the status quo. This tendency is evident in the privatization of land, the focus of this article. This article proposes an explanation for reform failures which suggests that some resistance to economic liberalization may derive from the efforts of state actors to protect the public good.

This article reviews the literature on postcommunist parties, which, by applying old Westernbased theories to a new and very different context, makes two important contributions to comparative politics. First, the literature stresses the importance of long-term and short-term historical legacies for the institutionalization of parties and electoral alignments; in trying to incorporate such legacies, it offers refinements to works on path dependency and political development. Second, the literature highlights the underinstitutionalization of postcommunist parties and thereby offers new insights—particularly on the party switching of electoral candidates—for studying the formation and consolidation of political parties.