Due to memory limitations, the World Trade Center towers were excluded from the New York Skyline, eerily enough the in-game story explanation was the Twin Towers were destroyed in a terrorist attack, a full year before the September 11, 2001 terrorist attacks on the United States.

The entire game takes place at night - apart from when the helicopter picks you up at the end of the Hong Kong missions, which occurs in daylight.

Due to the game's emphasis on allowing players the ability to search for different solutions to problems, it is actually possible to complete Deus Ex without drawing a gun.

Warren Spector wasn't very fond of the opening music. He was planning to tell the composer to come up with something else, but discovered that he couldn't get the tune out of his head. This convinced him to leave it as was.

The robots were inspired by the ED-209 robot from _RoboCop (1987).

Much of the game's content makes reference to Greek mythology or history.

Many of the elements present in the game are based on real conspiracy theories such as, The Illuminati, The Trilateral Commission, black helicopters, Men In Black, Area 51/aliens, FEMA camps, government engineered diseases/catastrophes & the Majestic 12.