Since the 2000s, local communities responsible for the management of common-pool resources, such as water or forest, have started to organize themselves regionally in order to promote their mode of community-based governance. Such a change in the scale of governance and in the agency of local communities reflects the on-going globalization of common-pool resources. Furthermore, it illustrates the evolving nature of global environmental governance that now includes new actors from civil society. Relying on a comparison of two transnational community-based networks in Latin America, the paper will first study the strategies and interests of such communities in the transformation of global norms affecting the management of their resources. Secondly, it will analyze the extent to which the relationships between those communal groups and nation states still remain decisive. Finally, it will question how this involvement of grassroots movements modifies both the essence of natural resources and their scales of governance.