Global climate change has become the collective action problem of our era. With the United Nations Framework Convention on Climate Change (UNFCCC) 2015 COP21 Meetings in Paris as the context, the author draws upon critical mass theory (CMT) (Oliver and Marwell 1988; Oliver, Marwell, and Teixeria 1985) in an attempt to yield greater understanding of the international community's ability to achieve climate stability as a global public good. Using CMT key elements of collective action production functions, group heterogeneity, and interdependence, the author explores the world's collective ability to mitigate greenhouse gas (GHG) emissions at the country level. Brief examples from Belize, Central America, and other small, vulnerable nations are used to focus attention on those countries that cannot make meaningful contribution to the collection action. The findings help illustrate why climate change is such a difficult collective action problem to address, what broad strategies might be required, and how to potentially achieve more targeted distribution of international resources.