As cities define our world in new ways every day, Penn Institute for Urban Research asked nearly dozen urban experts, “Why cities?”

When planned and managed sustainably and equitably, cities are engines of prosperity. In fact, cities contribute 70 percent of the world’s GDP. Yet, in many ways, cities have come to define and shape the overarching challenges of the 21st century: the speed and scale of their development is unprecedented. And housing the majority of the global population, cities are defining our world in new ways every day, raising complex questions about how to address the changes they bring to communities around the world.
With this in mind, and in conjunction with Penn's theme “Year of Why,” we asked more than a dozen urban experts, “Why cities?” In particular, we asked them to reflect on any or all of the following questions:
Cities throughout the world are growing in population and expanding in size—why is this? What are the most critical forces that are driving the new importance of urban centrality? How do they differ across the globe? How will urbanization impact inclusivity and sustainability? What are the common forces in global urbanization trends? How long will these trends last?
Their answers point to the centrality of cities in the future of our planet and its inhabitants, and shed light on how we can come to better understand and shape urbanization in the future.
FULL STORY: Expert Voices: Why Cities?

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