The coming of age of the start-up, grassroots, socially responsible hacker movement.

It has been predicted that more and more people will be immigrating to cities in the next decades. How will city governments be able to handle these demographic changes? Townsend, an expert on technology and smart cities, discusses the hope that lies within grassroots, socially responsible hackers who are taking challenges into their own hand-held devices—and who are solving the problems of the future today.