Dossiers in Marvel XP contain write-ups of characters and organizations, as well as stats on characters encountered in the game. They are unlocked by recruiting Heroes or through encounters in missions. There are 128 dossiers that can be unlocked in Avengers Alliance, out of a total of 144. The other 11 are found exclusively in Avengers Initiative.
The following are Dossiers that are unlockable in Avengers Alliance. Please refer to the Avengers Initiative Wiki for Dossiers that are unlocked by that game.