When testing first began in the late 1940s, it was discovered that the war heroes who participated in the testing process were quick to discard their personal belongings in favor of the testing uniform. They had little need for any items they said, and besides, they'll get it back at the end of the test. However, there was a noted hesitation in their handing over of their dog tags. An archived log displays one of these war heroes to show reluctance in giving up his dog tags.

"Test Subject has been stripped completely bare except for his dog tags and seems to display no shame in his exposure, despite the number of personnel in the room. Doctor has been admitted into the room for an inspection of physical health. The doctor has looked up from his notes and realized the test subject has not taken off his dog tags. The test subject grabbed his dog tags immediately after the doctor has ordered their removal.

'Why? They're just harmless little pieces of metal.'

'Do you know what the metal is exactly?'

'I'm sorry?'

'What is the composition of the metal? Is it 40% aluminum, tin, steel…?'

'I…I don't know.'

'Then for your safety I ask you to remove the dog tags. These tests can involve contact with substances that might be reactive to the compounds in the metal, and you'll get them back at the end along with your other personal belongings.'

'I know, but-'

'Remove your dog tags for your safety.'

'I…fuck. Fine.'

The test subject gritted his teeth and dropped the tags into the doctor's hands. The physical examination proceeded in a usual fashion after this exchange. See form 0001a for full report of physical health.

Note: For future dealings with military personnel, a psychological evaluation is requested for why they are attached to their dog tags. This is the 5th test subject to display this attitude. "

The request was granted, and the answer that each military man gave explained why they were more cautious in their testing than the test subjects with backgrounds as astronauts or Olympians. The evaluator who examined the records determined that the dog tags served as a reminder they could survive any situation. The fear they felt during testing was due to the removal of that one item that had survived with them, that also ensured that should they perish, the information about them would live on in some small way.

The first submission of this report to Cave Johnson did not aid the test subjects. In addition, his subsequent recording led to an even more unsatisfactory result in subjects experiencing the fear reaction more acutely. A second report with additional notes by Miss Caroline Jensen encouraged Mr. Johnson to give dog tags to test subjects. The standardized dog tags printed in Aperture Laboratories allowed for their use in test chambers, and with identical information from the previous dog tags engraved on the new ones, test results went up for all military personnel.

Cave Johnson then printed dog tags for all test subjects whether they were military or not with the Aperture logo, and Mr. Johnson stating that "This is our gift to you, for your participation in Aperture Laboratories advancement of science!" and before sending them on their way after the tests, he would add, "It's the only Aperture Laboratories products you'll get for free."

Following the missing astronauts case conducted by the Senate, and the following economic downturn of Aperture Laboratories, the first project to go was the production of the dog tags. Their assembly line was converted and expanded into the first turret factory building.

It wasn't until Cave Johnson's death that the idea of producing dog tags began to circulate among the rest of the Administrative Board. An excerpt of the first discussion follows.

"With the recent grant given to us by the U.S. Department of Transportation and the life insurance check for Mr. Johnson-"

"-May he rest in peace-"

"We now have a larger budget than anticipated this fiscal year. With the IRS breathing down our necks, we really can't afford to spend this money on anything that might be included frivolous, but all of our projects have adequate spending allotted to them. I suggest finding a morale booster with this money. Does anyone have any ideas?"

"How about we pay for bag-"

"-Dog tags."

"I'm sorry, Caroline? What did you say?"

"We had a project early on that included the production of dog tags for test subjects. It reported a positive increase in test subjects' results across the board. Turret Wing D1 still has some of the equipment inside. It'll be cheap to restart, and additional dog tags can be supplied to the U.S. military. Funding can go to the materials, and whatever we don't use should be allotted to emergency funding for future projects. That's what Mr. Johnson would have wanted."

-Long pause-

"That's not a bad idea. However, we'll need to make sure that will be the best idea. We'll let the idea sit for now, and at our next meeting, we'll discuss the budget and any other ideas that might come up. Meanwhile, Craig, I'd like you to run the numbers on every project and calculate the cost for this dog tag idea."

"Yes sir."

"Now to the matter of Mr. Johnson's Will-".

After several more meetings by the board, Caroline finally convinced them to begin production of the dog tags. It was a small gesture to the employees, and almost meaningless to test subjects who had no real experience with the military. The simple logo printed on the standard issue dog tags seemed trivial at first, but the board noticed an increase in productivity. The 'zoning out' so often seen in cubicle environments were now accompanied by a glance at the logo they wore around their necks (if they wore them as most employees did). The dog tags were not required to be worn for employees, but every member was given one. Test subjects enjoyed the 'souvenir' they were given along with their pay. Some test subjects were led to the Aperture facilities by seeing the tags around their friends' necks.

These observations weren't statistically significant, but it encouraged the board to continue the project, even after Caroline Jensen's retirement.

The dog tags became a part of the Aperture Testers uniform, but the employees slowly stopped wearing the tags as the keys they wore took their place. The dog tags instead became a symbol of the dedication of one's life to science. Most employees began to hang their dog tags in small dollar store frames and displayed them in their office. During retirement, employees would receive a specially engraved dog tag along with their farewell party, and cake.

Since Caroline Jensen retired before the dog tag tradition became a part of Aperture Laboratories, it was secretly decided amongst the board that the Genetic Lifeform and Disk Operating System, should receive her dog tags since its structure housed the memories of Caroline. The tags were inscribed with the phrase : "For Science" and "The Conscience of Us All" along with the Aperture Logo.

The tags shall be given to GlaDOS the day after "Bring Your Daughter to Work Day" in the event of a successful start-up. The likelihood that her start-up shall be successful has been confirmed by Dr. Henry Anderson, who states that "Her conscience has been installed. We plan to test it one last time before we give the all clear, but previous boot ups have been extremely successful, with GlaDOS indicating a desire to test. The new core seems to be working beautifully. I think we got it right this time."

The Bring your Daughter to Work day test-

Log corruption. Data needed.