This is the strongest book I have read on ET/UFO phenomena, largely because it addresses what I have suspected for some time - that the belief in such phenomena, whether or not there have been actual ET visitations, has been actively promoted and manipulated by certain agents of the military and intelligence communities around the world, principally the United States. Contrary to what another reviewer has intimated, I found this to be the strongest part of the book - unpalatable reading for those who want to believe, but it seems apparent that such belief has been the subject of high level manipulation; something that Vallee excellently illustrates. Knowledge of the operational history of leading intelligence agencies that can be picked up from reading any number of the many books on their Cold War and Second World War shenanigans I would argue allows one to see the hands of these people all over ufology. The book also does a fantastic job of warning about the dangers of these kinds of belief systems, and as mentioned by another reviewer, Vallee excellently makes the point that ancient Greek society was the victim of similar superstitions. It is dangerous to think that gains made in recent human history are irreversible, ignorance and fascism have an enduring power unfortunately. UFOs should be understood first and foremost as a fascinating social phenomenon, something that has always been an enormous industry, and this merits serious analysis in and of itself, nether mind questions of validity. Indeed, from their earliest days in the modern mass-media age UFOs have had an enormous hold on the popular imagination (think Orson Welles), and it is worth remembering that the books by the earliest `contactees' sold in vast quantities, propelling them into world-wide fame - this is not a phenomenon of the internet age only. Vallee's book works so well because it engages ET/UFO phenomena at the social level, something that few other works have done unfortunately. Ufologists sadly don't seem to realise that they would benefit greatly from turning their gaze inwards on their own field, and along with a limited number of books and articles written by social scientists on the subject, this book, decades on from its publication, continues to largely stand on its own against the tide.