CE-5, or a "close encounter of the fifth kind" — broadly defined as human initiated extraterrestrial contact.

Dr J. Allen Hynek was the director of project Blue Book, a military project supposedly tasked with researching UFO cases. Dr Hynek categorized the types of cases he was researching into three main kinds, which he labeled the first through the third kind. Although later in life Dr. Hynek admitted that the purpose of project Blue Book was to debunk all legitimate cases, the UFO community still uses his categorization today. Hynek's associate, Jacques Valle defined a forth type, and Dr. Steven Greer defined further a fifth type of close encounter.

Today we define the five main kinds of close encounters as:

• Close Encounters of the First Kind: Defined as visual sightings of an unidentified flying object seemingly less than five hundred feet away that show an appreciable angular extension and considerable detail.
• Close Encounters of the Second Kind: A UFO event in which a physical effect is alleged. This can be interference in the functioning of a vehicle or electronic device; animals reacting; a physiological effect such as paralysis or heat and discomfort in the witness; or some physical trace like impressions in the ground, scorched or otherwise affected vegetation, or a chemical trace.
• Close Encounters of the Third Kind: UFO encounters in which an animated creature is present. These include humanoids, robots, and humans who seem to be occupants or pilots of a UFO. This sub category was popularized by the movie of the same name.
• Close Encounters of the Fourth Kind: Defined by Jacques Vallee, Hynek's associate, as a UFO event in which witnesses experienced a transformation of their sense of reality.
• Close Encounters of the Fifth Kind: Defined by Dr. Steven Greer, CE-5 is actually a prototype hybrid project which has scientific research and diplomatic inter-species relations components. In this UFO event, it is humans who are initiating peaceful, bilateral contact with the ETs through conscious, voluntary and proactive cooperative communication.

So a CE-5 is actually more than just human initiated contact — there is both a scientific research aspect and a diplomatic, bilateral communication aspect. The scientific research aspect involves teams of people, or working groups, performing field research. The teams are not just out to "see" a craft, they are out there to initiate contact with the extraterrestrial peoples operating the craft, thus, the diplomatic aspect.

Although we have been talking about "UFOs" above, mostly because that is the term used in the definitions, in the CE-5 context they are not UFOs — as they are not unidentified, and they don't fly, at least not in the aerodynamic sense. We know they are either ET craft or man made anti-grav vehicles (yes, we have had them for some time) — or possibly conventional air/space craft or even natural phenomena. So not every light in the sky is an ET craft — and that is one reason we do field research — to learn to recognize the difference.

Instead of just reading on the internet about this topic, these teams of individuals go out and actually experience for themselves, so they can make up their own minds, and in the process they are participating in a peaceful diplomatic effort between humanity and these ET civilizations.