How can designers address the emergent self-organizing nature of complex urban environments? Designing the Complex City highlights how both an excess and a lack of design control might contrast the lively complexity of cities, their adaptive and evolutionary capacity. By using key concepts from systems thinking, complexity sciences, life sciences, cognitive sciences, and social sciences, the book frames a systemic spatial design approach aimed at enhancing the potential of different spatial design disciplines to navigate place-specific emergent transformations without overdetermining their formal outcome. A range of heterogeneous case studies, developing at different scales, show how embracing a design approach that is embodied, open-ended, contextually responsive, incremental and adaptive does not question the relevance of designers’ specific skills in shaping the physical structure of cities; it may rather increase their potential to effectively intervene in complex adaptive cycles of urban decay and self-regeneration.