Polarisation threatens the transformative capacity of cities at a time when collective plans for a more sustainable and resilient urban future are needed. The typical answer to polarisation has been to strengthen consensus building among stakeholders, but such approaches are known to lead to alienation, tensions with existing democratic institutions, and an increasing gap with legal practice. CONTRA explores how institutionalising productive conflict can increase the transformative capacity needed in the transition towards more sustainable cities. Through a comparative study of urban planning law and practices focused on climate transition in 4 countries (Belgium; Netherlands; Norway and Poland), we study how conflict is handled and investigate the connection with political and legal institutions to determine whether conflict is suppressed or actively used for sustainable transformation. We also test new ways to handle conflict. CONTRA pioneers a new model of living labs (Drama Labs) that uses theatre-based methods to experiment with productive conflict. Combining empirical investigations with action research through the Drama Labs, CONTRA responds to topic 2 and 3 of the call by building capacities for urban transformation grounded in urban liveability, inclusivity, and active community engagement, as well as improving non-physical infrastructure such as governance and regulatory processes.