The international nature of supply chains has led to the rise of private authority in regulating the environmental and social impacts of production, which companies frequently address through corporate social responsibility (CSR) in the form of private governance (PG). Despite its claim to establish "global" rules, PG usually has national origins, and multiple efforts to address the same issue from different national perspectives frequently coexist. Numerous studies have explored the impact of national business systems on companies' domestic CSR practices, yet little is known about what factors shape CSR practices like PG internationally. Therefore, this study seeks to understand how differing domestic contexts shape approaches to CSR in the form of PG in host countries. I explore this empirically through the comparative case study of competing PG initiatives in the post-Rana Plaza Bangladesh garment industry, uniquely conceived to govern companies' practices rather than certify products. It combines empirical findings with the comparative CSR literature to hypothesize about ideal types of PG organizing in US and European contexts. It extends the analysis to also account for other influential factors, such as stakeholder pressure, thus demonstrating how institutional and agentic factors amalgamate to shape firms' choices. By explicating linkages between international PG and its domestic context, as well as between the comparative CSR and PG literature studies, this study extends our understanding of how and why international PG practices and preferences vary for firms originating from different environments.