Facebook and Google, and other large technology companies, are some of the most powerful companies to ever exist. They touch every aspect of our lives, and decisions made by a few CEOs in Silicon Valley have a bigger impact on billions of people than their own governments. This lecture sets out the complicated landscape of Big Tech power, and whether it presents a threat to public power (governments, elections and democracy). The ongoing question of regulating the technology juggernauts may prove to be the great legal issue of our time.