AbstractHow can polycentric governance promote the development of ecosocial policies within existing policy systems? Through a study of green reforms of Danish vocational education, the paper argues that polycentric governance institutions are particularly useful at engaging constituent actors in innovation and constructive collaboration over reforming education programs to integrate ecological goals into vocational education. Combining significant autonomy for governance units and their nesting in a larger governance structure, polycentric governance helps address three key governance challenges: developing agreement among actors with clashing material interests about what green transformation entails; identifying how joint gains can be reached within a common vision of the development of the economy; and setting up an institutional structure that supports continuous adjustment to respond to technological advances and shifting social demands. Polycentric governance is, however, not a panacea. The state thus plays an important role in supporting autonomous governance units to develop ecosocial policies.