He teaches and pursues research on climate-change politics, global governance, multilateral treaty-making, and complex systems. Hoffmann is the author of the recent book Climate Governance at the Crossroads: Experimenting with a Global Response after Kyoto from Oxford University Press (2011) which explores the growing phenomenon of climate-governance experiments. He also authored Ozone Depletion and Climate Change: Constructing a Global Response from the State University of New York Press (2005) and co-edited (with Alice Ba) the volume Contending Perspectives on Global Governance: Coherence, Contestation, and World-Order from Routledge (2005).