In my lifetime the population of our planet has doubled. The way we live is changing faster than at any time in human history. More people around the world are moving into urban areas, and consequently cities are growing and changing fast. This new human planet requires a radical shift in the way we’re going to live together: How can we redesign cities? How can we use energy more efficiently? How can we plan infrastructure better? How can we move faster? How can we live healthier and happier lives? These challenges will require solutions from the next generation of scientists, thinkers and leaders. We need creative solutions wildly different from our old ways of thinking, which will rely on imagination and a bold new approach to science and engineering. With these new challenges will come exciting opportunities. We need brilliant young minds to think about tomorrow’s cities and redesign our world for the better.