Personal information management and privacy is a major and increasing challenge. New internet architectures will make people and their interactions more transparent to others than ever, and increase our digital footprints online. In a set of projects, we are studying user perspectives on anonymity and privacy online. We want to understand why people want to be anonymous online, what they understand about how the internet works, and how they learn about privacy and security tools through their social networks and personal experiences. We are using this understanding to explore new interfaces and interaction techniques for controlling personal information online and for informing national policy.