During the twentieth century spatial planning in the Netherlands obtained the status of being a worldwide benchmark. Two phenomena became especially famous: the Randstad Holland, as an example of a poly-nuclear metropolis, and the Delta works, as a masterpiece of hydraulic engineering. Both physical structures are strongly related to each other: the Delta Works (together with the Afsluitdijk and IJsselmeerpolders) contributed strongly to a rational organization of urbanization and industrialization of the western part of the Netherlands. Besides, the strong emphasis on major engineering works at the national scale stimulated a culture of state-organized top-down planning. Both concepts, Randstad and Delta Works, were strongly related to the concept of the Netherlands as a nation-state and to the rise of the Welfare State.From the start of the twenty-first century, the concept of the Welfare State and the concepts of Randstad and the Delta Works as expressions of a rationalized engineered urban landscape find themselves in a process of erosion. Changing economic conditions, changing ideas on nature and ecology, climate change and a changing planning-culture resulted in fundamental reconsiderations of these concepts. However, a total farewell to central planning and engineering will be impossible in this country. Many centuries of engineering have resulted in a situation where the survival of the country has become dependent on a continuation of a certain minimum amount of central planning and engineering. The mission for spatial planning, urban design and hydraulic engineering in the Netherlands is to find a new balance between decision-making at the large (national) scale and processes of self-organization at the regional and local scale.In particular, the flanks of the Randstad-territory are examples of a process of reconsideration and redefinition of goals and content of spatial planning, hydraulic engineering and urban design in the Netherlands: at one side the New Town Almere east of Amsterdam, and at the other side the South-west delta, south of Rotterdam. Both cases can be considered as important laboratories, where attempts to define new balances between urbanization and natural landscapes, and between top-down and bottom-up developments, are tested.