This chapter defines a global commons including: (1) those oceans and seas outside of any single country’s political domain, (2) our globally circulating atmosphere, and (3) the various river systems and other land masses, such as mountain ranges and large forests, that either cross political boundaries or are outside the political domain of any single country. The political difficulties of forming the collective imperfect duties (duties of virtue) necessary for managing these global commons are reviewed. Examples of some of the world’s more significant forests and river systems are examined as illustrations. These “difficulties” can be mitigated by the world’s ability to generate the necessary data for facilitating a political solution, and by the application of the “fairness criteria” that were developed and explored in the chapters above. The roles of three international environmental advocacy organizations (EAOs)—The Nature Conservancy, The World Wildlife Fund, and Greenpeace—in developing awareness of the tragedy of the global commons, and in developing some remediation efforts, are also reviewed.