This paper explores the differing approaches to conceptualizing interregionalism that have stemmed from two distinct periods in the evolution of these group to group structures: the periods of the old and the new in interregionalism. It notes the gap evident in the field of interregionalism the form of theory-guided comparative studies, and questions whether the field is yet in a position to begin filling this gap. In addressing this question, it explores the actorness-interregionalism framework of the post-bipolar period of new interregionalism, and the patterns of engagement that have begun to emerge in interregional EU-Asia relations, both in the bilateral interregional (EU-ASEAN) and transregional (ASEM) variants. It contends that these patterns are gradually becoming evident beyond the EU-Asia context, making the frameworks extrapolated from EU-Asia relations a potential foundation stone for the emergence of theory-guided comparative studies.