Every quest that appears in your Pip-Boy grants an achievement (on the Xbox 360 and PC) or a trophy (on the PlayStation 3) upon completion in base game only. Unmarked quests do not provide achievements/trophies. Side quests in Point Lookout and Broken Steel do not provide achievements/trophies either. Most of the quests in Fallout 3 either involve or can be completed with a combat situation (e.g. killing Vance and The Family in Blood Ties). There are 59 quests (main, side and repeatable) in the base game. The 5 add-ons provide for a further 35, which makes the total 94 quests.