The domed U.S. Capitol has been rebuilt and enlarged many times under the direction of the person serving as Architect of the Capitol. Alan Hantman, who held the position from 1997 to 2007, shares insights into how the Capitol works as a physical space, who runs it, and how and why decisions are made about security. Hantman recounts memorable security threats, including the 1998 fatal shooting of two police officers and the evacuation of the Capitol on 9/11 as a hijacked airplane approached.