Sightings of unidentified foreign objects (UFOs) have been reported throughout the centuries—most of them given a religious interpretation. Since World War II, however, there seems to have been a drastic increase in the number of sightings. We have enough data—both visual and photographic—on some of these sightings to know that the phenomenon is unambiguously extraordinary and clearly inexplicable in modern terms. The author examines UFO brightness, size, and maneuvers, and discusses the frequency and location of sightings. He ends by suggesting the need for more standardized reporting on UFOs, so that times and locations of appearances may be anticipated and badly needed objective data may be obtained.