Introduction: Commons research in the 21st century and beyond Sheila Foster and Chrystie Swiney; Part I. Revisiting the Origins and Evolution of Commons Thought: 1. Linking the origins and extensions of commons theory William Blomquist; 2. The tragedy of Garrett Hardin's commons Andrew P. Follet, Brigham Daniels, Taylor Petersen; 3. Kinship and commons: the Bedouin experience Haim Sandberg; Part II. Averting New Tragedies: 4, Averting tragedy of the resource directory anti-commons Greg Bloom; 5. Time and tragedy: the problem with temporal commons Blake Hudson; 6. Transforming climate dilemmas from tragedy to cooperation Bryan Bruns; Part III. New Forms of Contested Commons: 7. Urban public housing as a commons Andrea Mcardle; 8. Humanitarian aid as a shared and contested common resource Michelle Reddy; 9. The economic system as a commons: an exploration of shared institutions John Powell; Part IV. Urban Landscape and Infrastructure as a Commons: 10. Seeing New York City's urban canopy as a commons: a view from the street Rebecca Bratspies; 11. City as commons: the case study of Bologna Elena De Nictollis and Christian Iaione; 12. Urban commons architecture: collaboration spaces innovating learning within cities Sofia Croso Mazzuco; Part V. Reassessing Old and New Institutions for Collective Action: 13. Business improvement districts and the urban commons Alexandra Flynn; 14. To have and to hold? Community land trust as commons Barbara Bezdek; 15. Ostromian logic applied to civil society organizations and the rules that shape them Anthony Demattee and Chrystie Swiney; 16. A conceptual model of polycentric resource governance in the 2030 district energy program Erik Nordman; Part VI. Managing and Restoring the Commons: 17. Management of facilitated common pool resources in India Pradeep Kumar Mishra; 18. Social environmental dilemmas and governing the commons: the Itanhém river basin in Southern Bahia, Brazil Herbert Martins and Fernando Rios De Souza; 19. Social trust, informal institutions and community-based wildlife management in Namibia and Tanzania Daniel Ogbaharya; 20. Restoring the commons Itzchak Kornfeld; Part VII. Law, Legal Theory and the Commons: 21. Prior appropriations as a response to the tragedy of the commons Robert Abrams; 22. Using the public trust doctrine to manage property on the moon Hope Babcock; 23. A biotechnology regulatory commons problem David Forman; 24. Can affirmative action offer a lesson in fighting enclosure? Sheldon Bernard Lyke; Part VIII. Technology, the Internet and the Future of Commons Governance: 25. Can technological change weaken the robustness of common-property regimes Maija Halonen-Akatwijuka and Evagelos Pafilis; 26. Internet governance in the digital cold war Scott Shackelford and Angie Raymond.