Design principles for efficient and legitimate differentiated integration schemes

Despite a considerable scholarly interest in differentiated integration (DI) as a design option, the literature on the topic is fragmented and unsystematic. The present paper fills this gap by developing a novel analytical framework to inform the assessment and design of international integration schemes based on seven evaluative criteria (feasibility, overall benefits, substantive fairness, procedural fairness, acceptance, sustainability, and overall desirability) and related design principles (maximization or satisfaction) and empirical indicators. It then applies it to the available theoretical and empirical literature on various models of international integration to identify the comparative strengths and weaknesses of internal DI and external DI. In light of the predominantly normative and highly controversial nature of the assessment process, the analysis suggests that the best way to design efficient and legitimate DI schemes is to ensure their responsiveness to democratic preferences and decision-making procedures at the national or EU level.This publication is part of the InDivEU project which has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement number 822304. The content of this document represents only the views of the InDivEU consortium and is its sole responsibility. The European Commission does not accept any responsibility for use that may be made of the information it contains