Framing Urban Systems and Planning Concerns as a Multilevel Problem: A Review of the Integrated Urban System Models with an Emphasis on Their Hierarchical Structures

Metropolitan economies have been pounded by enormous structural changes in the last three decades. This structural change has manifested itself in a different spatial organization of production within metropolitan areas. This article examines how such complex interactions are described in the integrated planning support models to simulate regional as well as subregional growth dynamics. It focuses on the way in which vertical integration is handled. It begins with a review of the integrated framework. The review suggests that strict top-down integration is a dominant approach, although there are various strategies to model the overall dynamics of the macroeconomic changes and the evolution of spatial structure, respectively. Finally, it introduces some alternative ways of modeling vertical integration that try to overcome the critical limitations of the strict, top-down approach and to go beyond the earlier characterization of a top-down/bottom-up dichotomy.