The delta region between Rotterdam and Antwerp is a prime example of an area where spatial developments face increasing complexity. Local initiatives for developing urban expansions, recreation areas, nature and industrial complexes must harmonize with measures such as adequate flood protection, sufficient freshwater supply, restoration of ecosystems and large-scale infrastructure over the long term. This complexity demans a new approach to spatial planning and design. This book is the result of a research project that aimed to develop such a new planning practice. The research was carried out in collaboration by a consortium of universities, centres of expertise, and engineering and design firms. The research conceived of the Southwest Delta of the Netherlands as a laboratory for the new approach, which has nonetheless also proven relevant to other regions dealing with a similar level of complexity.