The authors present the state of the art in the rapidly growing field of visualization as related to problems in urban and regional planning. The significance and timeliness of this volume consist in its reflection of several developments in literature and the challenges cities are facing. First, the unsustainability of many of our current paradigms of development has become evidently clear. We are entering an era in which communities across the globe are strengthening their connections to the global flows of capital, goods, ideas, technologies and values while facing at the same time serious dislocations in their traditional socioeconomic structures. While the impending scenarios of climate change impacts remind us about the integrated ecological system that we are part of, the current discussions about global recession in the media alert us and make us aware of the occasional perils of the globalized economic system. The globally dispersed, intricately integrated and hyper-complex socioeconomic-ecological system is difficult to analyze, comprehend and communicate without effective visualization tools. Given that planners are at the frontlines in the effort to prepare as well as build resilience in the impacted communities, appropriate visualization tools are indispensable for effective planning. Second, planners have largely been slow to incorporate the advances in visualization research emerging from other domains of inquiry. Findings of research in other disciplines, such as graphic design, geography and cartography also lead to the development of new forms of visualization and communication.