The adoption of the “Paris rulebook” at Katowice in late 2018 marks the most significant milestone in international climate policy making since the adoption of the Paris Agreement in 2015. Through a package of decisions, Parties to the Paris Agreement fulfilled almost all of the Paris mandate and moved towards the full implementation of the treaty. With the exception of the discussion on the future of carbon markets, negotiators managed to find common ground across negotiation items ranging from mitigation action to ensuring transparency and follow-up, including through “global stocktakes”, climate finance and technology transfer. Most obligations will apply to all countries, replacing the “bifurcation” of the Kyoto Protocol with a common set of rules for all Parties. Developing countries can make the case for additional time and assistance to comply with the full set of requirements. Several matters are left for future sessions – concerning, in particular, the harmonization of the timeframes of mitigation goals, markets and finance mobilization– and structural challenges – not least concerning the integration of non-state actors – remain. However, in building on accountability, trust, and compliance through facilitation, the new Paris rules may ultimately prove decidedly more robust and sustainable than those of the Kyoto Protocol.