The Half-Life: Opposing Force soundtrack was composed by Chris Jensen; it was reused for the Half-Life: Blue Shift soundtrack. However the Half-Life soundtrack by Kelly Bailey replaces the original one in the Steam releases of Opposing Force and Blue Shift.
Many of the original tracks had no name on the Opposing Force disc, but received one on the Blue Shift disc. Additionally, most previously named tracks received a new name on the Blue Shift disc as well. When a track has multiple titles, the Opposing Force title is listed first.
|“Scientific Proof”||Played during the opening scene aboard the Osprey||Blue Shift Track 11|
|“The Awakening AKA Orbit”||Blue Shift Track 13|
|“Name”||Blue Shift Track 14|
|“Spooky Oozings AKA Listen”||Blue Shift Track 15|
|“Spooky Monestary”||This is the only track to not be used in Blue Shift, though it may have been intended to be Track 16, "Fright"|
|“Storm”||Blue Shift Track 17|
|“Spectre of Limbo AKA Trample”||Blue Shift Track 18|
|“Race from Doom 2 AKA Bust”||Blue Shift Track 19|
|“Temple of Limbo AKA The Beginning”||Blue Shift Track 1|
|“Wastes of Limbo AKA Lost in Thought”||Blue Shift Track 2|
|“Danger Rises”||Blue Shift Track 3|
|“Soothing Antagonist”||Blue Shift Track 4|
|“Stroke of Midnight AKA Run”||Blue Shift Track 5|
|“Open the Valve”||Blue Shift Track 6|
|“Tunnel”||Blue Shift Track 7|
|“The Ticking Timebomb AKA Chamber”||Blue Shift Track 8|
|“Maze”||Blue Shift Track 9|
|Untitled Track||This track is called "Opposing Force: Track 19" on the Opposing Force disc, and "Blue Shift: Track 10" on the Blue Shift disc.|
|“Planet”||This is the song played over the final credits.||Blue Shift Track 12|
The original soundtrack can be used on Steam by converting the audio parts of the WON games into the mp3 format and placing them in the proper audio folders. Steam will also recognize the audio tracks of the original Opposing Force CD-ROM.