Full list of all 40 Them and Us achievements.
The base game contains 19 achievements, and there are 2 DLC packs containing 21 achievements.
Fight a Walker.
Die for the first time.
Kill all the enemies inside the mansion.
Unlock all rooms from the Mansion.
Finish the game without saving.
Obtain all weapons.
Finish the game in under 3 hours.
Finish the game on Hard difficulty.
Finish the game on Professional difficulty.
Finish the story in fixed camera mode.
Finish the game in Over The Shoulder mode.
Find all documents in the game.
Unlock all costumes.
Finish the story with an S+ Rank on "Professional".