There are thousands, every year. In every corner of the world, sightings of Unidentified Flying Objects - UFOs in Italian, UFOs in English - are hardly counted anymore. Eyewitnesses include civilian and military pilots, astronauts, politicians and scientists. These unknown craft seem to outperform even the most modern fighter jets with their seemingly unapproachable technology. The Top Secret files now declassified by governments say so. Also from ours, which in 1978 commissioned the Air Force to monitor Unidentified Flying Objects. And precisely for a matter of national security, almost everywhere ministries of defense, armed forces and secret services have been involved in the study of UFOs. With what results? What does the public really know about it? Are they hiding something from us? This volume examines the phenomenon from various points of view, analyzing the documents, giving the floor to the witnesses, examining even the most disconcerting theses, to try to shed light on the mystery.