TSCM (Technical Security Countermeasures) is the U.S. federal government's abbreviation for electronic counter-surveillance. This talk is about the art and science of TSCM and how it's used to actually catch spies in the act. It will include photos and visual aids about how a TSCM professional goes from a mere hunch to tracing the spy right to their listening post. While this presentation will obviously be unclassified, it will focus on facilities used by the U.S. intelligence community and DoD contractors, methods used to "sweep" these targeted locations for electronic surveillance, and how actual "bugs" were found. It will include sufficient technical detail to enable the HOPE audience to apply technical search methods to their own locations and communications equipment. This will be a distinctly hardware or physical layer oriented presentation, which will assume a limited knowledge by the attendee of the physical aspects of technical espionage. The presentation will cover an actual espionage operation uncovered using these methods, and what was done to exploit the spy who was exploiting the bug, and how they were neutralized. Methods used for frustrating technical spies, including state actors, will be discussed, as well as methods for identifying an informant within a group. The concept of "nexus" will be discussed as it applies to counterespionage and how scientific methods are used to locate a nexus between the target and a pathway, between the pathway and the listening post, and from the listening post to the spy. This talk is designed to have a broad appeal, and will include details about bug sweeps and spy hunting jobs that the speaker recently led. The audience may become a bit paranoid learning how vulnerable they are to illegal electronic eavesdropping, but methods will be presented on how they can lawfully enhance their privacy. Legal protections that U.S. citizens have against government eavesdropping, and how to frustrate state-sponsored eavesdroppers, will be discussed - as well as how and where to look for bugs and other eavesdropping devices and how to use improvised methods when only low-tech tools are available. Highlighting this talk will be examples of four specific bug sweeps (two CIA cover operations and two DoD contractor locations) and, while it will not include classified information, the U.S. government will not be amused. Photographs, blueprints, drawings, cable traces, spectrum analyzer screenshots, and related measurements will be shown so the audience can grasp the art and science of effective TSCM.