Deus Ex

The soundtrack of Deus Ex, composed by Alexander Brandon (primary contributor, including main theme), Dan Gardopée ("Naval Base" and "Vandenberg"), Michiel van den Bos ("UNATCO", "Lebedev's Airfield", "Airfield Action", "DuClare Chateau", plus minor contribution to some of Brandon's tracks), and Reeves Gabrels ("NYC Bar"), was praised by critics for complementing the gritty atmosphere predominant throughout the game with melodious and ambient music incorporated from a number of genres, including techno, jazz, and classical.

The music sports a basic dynamic element, similar to the iMUSE system used in early 1990s LucasArts games; during play, the music will change to a different iteration of the currently playing song based on the player's actions, such as when the player starts a conversation, engages in combat, or transitions to the next level. All the music in the game is tracked - Gabrels' contribution, "NYC Bar", was converted to a module by Alexander Brandon.