This month, the London School of Economics (LSE) hosted its 10th annual UrbanCities debates, a forum where world leaders in the field of urbanism come together to discuss their views on the subject and its relative disciplines (mainly architecture). This year AN caught up with Design Museum curator Deyan Sujic, Norman Foster, and Chilean architect Alejandro Aravena, among others for the debate. "Eighty percent of a country's total GDP is generated from urban areas," Joan Clos, executive director of Un-Habitat, said at the conference. With this, he argued that "transaction costs can be reduced by the availability of labor," supposing the labor supply is within the vicinity of the production area. For this to happen, though, urban planners must focus on the "human scale," focusing their attention on streets, not roads. "Thirty to 35 percent of urban environments are made up of streets, " Clos added. Streets, density, and pedestrianisation would be dominant themes for the debates. Norman Foster continued that theme, clearly setting a hierarchy in the built environment. "Beyond architecture, infrastructure is more important," he said. In his talk, Foster seemed to be both acknowledging his role as an architectural figurehead, but also at how his work may be seemingly powerless to solve the urban problems faced today. "The quality of infrastructure determines the quality of our lives," he added, and "infrastructure is inseparable from economic prosperity." "I have no power as an architect, none whatsoever," lamented Foster in a recent interview with the Guardian. He noted that government policy has a much bigger impact on the shape of the built environment than being an architect does. Citing the population density of the South London suburb of Southwark, Foster said how in 80 years, the density has in fact decreased from 20,550 people/km2 in 1901 to 2,232 people/km2 in 1981. Foster, building on Clos's remarks, emphasized the importance of density, with its connection to energy consumption. Using Atlanta as a tragic example of failure in this respect, he compared the sprawling U.S. city to its opposite extreme, Hong Kong, in how much the two cities differ in almost every aspect. As demonstrated in Atlanta, high density and energy consumption are negatively correlated. Needless energy is wasted in simply moving around, such as getting to work, bringing the previous conversation about proximity—or lack thereof—of the labor supply full circle. Foster clarified this need for density with a call for better public space to offset potential overcrowding. He cited the classic example from New York, saying that "Central Park [is] probably the only park built for the social good." Foster contrasted Olmsted's green space to London's parks that are just old royal hunting grounds, not actual spaces constructed on behalf of the public. Aravena was also complimentary of New York, claiming that "Manhattan is the most productive piece of of urbanism in the world." LSE Professor Ricky Burdett pointed to the flexibility of New York's built environment. "Places in NYC designed for one thing are now used for another," he said, illustrating how diverse and adaptive the city's architecture and infrastructure had become. Manhattan, bound by its physical geography, had to change over time to stay relevant. Aravena added how restraints in design can be beneficial to the process, particularly with urbanism, citing how Philadelphia was literally planned overnight by William Penn. "Time, for urbanisation, is a good restraint," Aravena said, adding that the influx of migrants into European cities could be "windows of opportunity," opening up scenarios similar to when Penn had to plan a city in very little time. Going back to Atlanta, Foster again tackled the infrastructure problem, touting High Speed Rail as an urban palliative that can take on functional and aesthetic roles as well as be used as a tourist destination. Concluding the talk, Joan Clos lamented how a "loss of identity, down to unrestricted development," where developers have too much space and so many material construction methods that have come at the cost of indigenous ones. In doing so, he posed the question: Does globalization mean the demise of the vernacular? The answer continues to play out across the globe.