The social aspect of circular economy (CE) is an emerging research stream in the CE scholarship. Yet this has not been entirely explored and investigated. There are calls from research around the conception of ‘social aspects’ and its underlying socio-political dynamics in the circular economy transitions. Accordingly, the collection of studies in this dissertation includes a series of works on the social aspects of a CE that reveal the social CE transition through a multi-level framework: (a) social logics (macro-level), (b) inter-organizational dynamics (meso-level), and (c) individual agency (micro-level). Study 1 – macro-level – is designed to address structural obstacles caused by the current CE paradigm, focusing on how to embed social logic into the CE transitions. This study discusses the trade-offs and synergies among eco-efficiency, ecological, and social logics through the proposed four-type hybrid circularity, illustrating the arguments with four brief case studies. Study 2 – meso-level – aims to unveil cross-sectoral organizing in the transition processes: the collaborative and contested interplay between civil society organizations and companies. This study develops the concept of ‘CE boundary work’ and outlines three approaches, i.e. campaign-based, resource efficiency-based, and circular design-based, to understand the underlying dynamics. Both studies are designed for theoretical contribution to the CE scholarship. Study 3 – micro-level – is positioned at the intersection of theoretical and empirical implications, which aims to empirically investigate the role of individual agency, namely, internal activism, in driving organizational change. Building on the conception of organizational boundaries, this study shows how different forms of internal activism shape firms’ motives for embracing CE principles. Afterwards, three standalone studies have provided implications, directions for further research, and contributions to knowledge around social CE transition, respectively.