Eurpean Union (EU) environmental policy has increasingly advanced multi-level governance (MLG) to improve policy implementation. MLG approaches mandate (sub-) national planning and introduce functional governance layers to match the biophysical scale of environmental problems. Whereas the literature on policy implementation has focused on the challenges posed by multi-level systems, the described EU approach relies on MLG as a strategy to better policy implementation. This contribution studies the implementation of EU air quality directives, drawing on all 137 German air quality and action plans, to explore how requirements of multi-level implementation are delivered on the ground. Overall, we find the model of implementing air quality policy through MLG of limited success. In particular, sub-national policy-makers use their new planning competencies but struggle to implement functional governance layers. Mirroring experiences from neighbouring EU policy fields, our findings raise the broader issue of ‘failed’ implementation versus a still untapped potential for adaptation and governance learning.