Seth Shostak discusses the search for extraterrestrial intelligence and SETI's ongoing efforts to detect alien signals. Shostak examines the methodology of scanning the cosmos for radio transmissions from technological civilizations. The conversation explores the Drake equation estimating the number of communicating alien civilizations in our galaxy. Shostak discusses SETI's findings so far and the challenge of distinguishing alien signals from natural radio sources. The discussion addresses the Fermi paradox and why we haven't detected obvious extraterrestrial intelligence despite vast numbers of stars. Shostak examines what types of signals SETI listens for and how to recognize artificial transmissions. The broadcast explores the implications of detecting an alien signal and protocols for how humanity should respond. Shostak discusses the probability of intelligent life existing elsewhere and whether we are truly alone. The conversation addresses criticisms of SETI and whether resources should focus on different search strategies. Shostak examines what SETI reveals about humanity's place in the cosmos and the likelihood of contact.