The European Union (EU) will review its institutions during 1996 in the course of an intergovernmental conference. This conference will emphasize more explicitly than in the past the EU's political identity.' In light of the negative public fallout from the Maastricht Treaty ratification, concerns of political legitimacy, notably the issue of more power for the European parliament, will undoubtedly attract attention. This conference takes on added significance as the EU, having expanded its policy scope into areas once reserved for national governments, exhibits traits resembling those of state. Questions of legitimacy, on the one hand, and growing state-like properties, on the other, require an analysis that links these two political developments. Research on political development and regime legitimation has emphasized the role of political parties.2 Might there be connection between future EU integration and the organizational development of transnational parties? As calls for enhanced participation and legitimacy in the EU are raised, do transnational parties acquire greater salience than since their establishment in the 1970s? This article argues that the role of transnational parties in EU politics should be rethought. Although present party development may be seen as dependent variable of European integration,3 evidence of organizational innovation among transnational, notably Socialist and Christian Democratic, parties points to its growing relevance in the EU. Partisan perspectives in EU policymaking can both influence and legitimate further integration. Transnational party development has reached stage where it may begin to shift from being dependent to an independent variable in European integration. Analysis of European party politics requires attention to the institutional environment. A European political system has emerged, even if it is a partial polity, without an independent legitimacy or direct political authority.4 This Europolity does not operate along the lines of generic parliamentary system, nor is it clearly federal territorial entity. Nevertheless, EU institutions have developed logic and relationship to national actors that are more than epiphenomenal and in fact are part of an emerging system of European governance.5 Much as the institutional map of this system is unique, so too will be the role of transnational parties, which will approximate network coordinators within the institutional complexity of this Europolity.