What's it like to spend a career as a cyberdefender for the DoD and the nation, but homed inside of an intelligence agency? In this talk, I'll offer a historical and personal perspective based on 35 years at the National Security Agency as a vulnerability analyst for the defense, from junior analyst to executive manager. The common element across my career was the search for vulnerabilities in the name of defense - finding them, making sense of them, leading organizations to find them, and then translating that knowledge into action to prevent or manage them. I'll share lessons learned as cyberdefense evolved from a focus on mathematics and cryptography to systems and software; and from government security to a global internet. And we'll focus on the mission, technical, and cultural interplay of cyberdefense and offense/intelligence as it played out at NSA. War stories, culture clashes, bureaucratic mazes? Of course! But in the end, better security for all.