There is a crack in everything — that’s how the light gets in Leonard Cohen, Anthem In an era often characterized as one of growing convergence of the laws governing criminal activities in different countries, the issue-area of cannabis policy undergoes processes of fragmentation and polarization. Some countries continue to criminalize all forms of medical and recreational uses of cannabis. Others have sought to “separate the market” for cannabis from that of other drugs by decriminalizing the possession of small amounts of marijuana, authorizing its use for medical purposes, and establishing administrative measures for taxing and regulating the commercial sale of the drug. This Article explores the causes and consequences of the decline of the transnational legal order of cannabis prohibition. It shows how the erosion of the regulatory capacities of this transnational legal order reflects deepseated political conflicts over the legitimacy of prohibition norms in this field. It analyzes the ways in which conflicting regulatory approaches become institutionalized as a consequence of the structural mismatch between the actors framing the meaning of cannabis prohibition norms at the international level and the actors implementing these norms in national and local contexts. Finally, the Article shows how this transnational legal order has created path-dependent trajectories of legal change that continue to shape domestic drug policies.