Cities are full of districts that planning documents underestimate — close to the centre, historically active, but classified below their potential. This lecture argues that urban design is the missing ingredient in most urban regeneration strategies: not as decoration, but as the spatial framework that makes economic transformation possible. Drawing on two KCAP projects — the Werkstadt Zürich, a former SBB railway workshop becoming a hub for urban manufacturing, and Fellenoord in Eindhoven, where the Brainport ecosystem is finding its urban home — the lecture demonstrates three conditions for successful productive district regeneration: identity built from existing fabric and users, mix as an economic strategy that puts proximity and encounter at its centre, and a shared spatial framework that guides transformation in districts with fragmented ownership and phased development. The lecture closes with the Muscat context: the opportunity that exists when inner-city districts with existing character and a working economy are given the right spatial framework before the plans are fixed.Anouk Kuitenbrouwer is a Lecturer at ETH Zurich and a Partner at KCAP, specialising in urban design and masterplanning for urban transformation.