Thread:Vorknkx/@comment-26005008-20150803211106/@comment-1496755-20150804050522

Yes, just as with any other game series.

I consider the official mission packs to be canon as well, although in case of a contradiction, the game itself takes precedence over the mission pack.

For example, there is a certain inconsistency between the ending of Q2: Ground Zero and the story of Q4, but Q4 takes precedence due to being a full game and not a mission pack. The contradiction is resolved in favor of Q4.