This chapter develops some reflections presented at the ISTR webinar series The Future of Third Sector Research under the topic “Changes and Challenges in Civil Society Definitions: Learnings from International Perspectives and Dialogue” in April 2023. It reflects my perspective as an international civil society researcher based in Poland and some of my interests including social movements and their organizational platforms, leaders’ motivations, and the impact of technologies on the civic life. As a result, I try to underline the importance of reflecting on the dominant definitions of civil society from the point of view of growing complexity of the field and the involved struggles between its actors. The starting point is the tension between civil society as an object of measurement (embodied in John Hopkins project or UN Handbook) and the concept of civil sphere as defined by Jeffrey Alexander and embodied by various collective practices observable around the globe. In the context of modern discussion on the shrinking of the civil sphere (Siri Hummel et al.) and the rise of new forms of (digital) activism, the boundaries of civil society are being questioned repeatedly.