As a 15 year old growing up in France, Vallée and his mother sighted a UFO. As he earned degrees in astrophysics (Sorbonne, University of Lille) and computer science (PhD, Northwestern), he continued to investigate the phenomenon -- scientifically. He has authored many books on the UFO phenomenon.
You may remember the French astronomer in "Close Encounters of the Third Kind." Played by Francois Truffaut, the character is based on Vallee. FTR, J Allen Hynek played a cameo.
Dr. Vallée was among the first to apply information science to the UFO phenomenon. He believes the phenomenon is real and exhibits an unknown intelligence that operates in ways that we are only beginning to understand. He also wrote the data reveal a more complicated phenomenon than mere visitors from outer space.
He finds the extraterrestrial hypothesis (ETH) to be too simplistic to explain many, if not most, varieties of experiences and aspects of the phenomenon, including the absurd appearance, behavior and impact of the objects and their often-affiliated occupants on witnesses, society, and culture.
From his first to his latest, all his works are great reading for people interested in the UFO phenomenon. In "Passport to Magonia: From Folklore to Flying Saucers," he puts things into historic perspective. Whatever it is UFOs are or represent, they've been with us as long as memory and history serve.
https://www.librarything.com/work/207795
Dr. Vallée said he would be disappointed if UFOs turned out to be simply alien visitors. They may be from another dimension or be interdimensional travelers, time travelers or visitors passing through a wormhole from another universe entirely, they may even be manifestations of the cosmos itself. However, it it is "Little Green Men" from Planet X, Vallée fears humanity might get the visitors we deserve. Dunno how things could be worse, we got drumpf.