The rationalist approach to agenda setting assumes that European Union (EU) institutions and member states have stable preferences which they pursue in the EU decision-making process. Strategic behaviour approaches to agenda setting were extended to the study of other actors in the EU system, such as the Governing Council of the European Central Bank or the European Convention that had been tasked with drafting the constitutional treaty. The punctuated equilibrium theory was developed to explain the dynamics and mechanisms of policy change. One central direction in the empirical analyses of agenda-setting processes in the EU focuses on different actors or venues of policy making. Research should also consider and elaborate on new methodological approaches for disentangling driving factors behind the composition of broad agendas of EU institutions. Agenda-setting research is increasingly utilising policy agendas as a 'tracer liquid' for studying the political system through the circulation of policy issues.