This paper examines the need for a return to a systemic,holistic,and normative approach to designing human settlements that has been neglected with the decline of the Welfare State and the shift to iecemeal,freewheeling,marked-based development during the unprecedented explosion of construction in the last thirty years.The need for a change is brought about by the current ecological and economic crises linked to a high degree to the current belief that the quality of cities emerges from the added-value of individual buildings or through the assemblage of individual structures put together like a building.This paper argues that a city is not like a building.The contemporary city is characterized by an unprecedented number of problems.These problems cannot be handled by individual good will or simple preventive or corrective actions by architects and developers as it has been done the last three decades.What is needed is an overall systemic framework of planning that ① is driven by normative criteria,② can handle a high degree of complexity and interdependence of factors,and ③ can deal with unanticipated,unintended,long-term irreversible environmental impacts that characterize the “third ecology,” the inseparable complex of the natural and the human-made. This paper examines the need for a return to a systemic, holistic, and normative approach to designing human settlements that has been neglected with the decline of the Welfare State and the shift to iecemeal, freewheeling, marked-based development during the unprepared explosion of construction in the last thirty years.The need for a change is brought by by current current ecological and economic crises linked to a high degree to the current belief that the quality of cities emerges from the added-value of individual buildings or through the assemblage of individual structures put together like a building.This paper argues that a city is not like a building.The contemporary city is characterized by an unprecedented number of problems.These problems can not be handled by individual good will or simple preventive or corrective actions by architects and developers as it has been done the last three decades. What is needed is an overall systemic framework of planning that ① is driven by nor mative criteria, ② can handle a high degree of complexity and interdependence of factors, and ③ can deal with unanticipated, unintended, long-term irreversible environmental impacts that characterize the “third ecology,” "the inseparable complex of the natural and the human -made.