Bill Kerr, a professor at Harvard Business School, studies the increasing importance of talent clusters in our age of rapid technological advances. He argues that while talent and industries have always had a tendency to cluster, today's trend towards San Francisco, Boston, London and a handful of other cities is different. Companies need to react and tap into those talent pools, but moving the company to one isn't always an option. Kerr talks about the three main ways companies can access talent. He's the author of the HBR article "Navigating Talent Hot Spots," as well as the book "The Gift of Global Talent: How Migration Shapes Business, Economy & Society."