Full list of all 41 The Bureau: XCOM Declassified achievements. It takes around 25-30 hours to unlock all of the achievements in the base game on Windows.
The base game contains 34 achievements, and there is 1 DLC pack containing 7 achievements.
Get 40 kills on Flanked enemies within a single campaign
Now, it's time to end this
Take down 20 Outsider Shields using laser-based guns within a single campaign
Reach Rank 10
Retrieve and escape with information on the enemy base
Complete 6 Minor Operations within a single campaign
Complete 6 Dispatch Missions within a single campaign
Confront the Outsider Leader
Complete all Investigations in the base within a single campaign
Closure
Get an agent of each class to Rank 5 within a single campaign
Defeat a Titan
Infiltrated the Outsider Tower
Reach Rank 5
Perform 15 unique scans within a single campaign
Give 150 commands to agents while in Battle Focus within a single campaign
Complete your first Dispatch Mission
Complete your first Minor Operation
Customize an agent
Secured the package
Defeat a Sectopod
Defeat a Muton
Take an agent of every class into the field within a single campaign
Get 20 Headshot kills with any gun within a single campaign
Escaped Groom Range
Complete the game without a single agent bleeding out
Complete an entire Operation without the player firing a weapon or using a grenade
Beat the game on Commander difficulty without ever changing it
Attach 10 Sticky Grenades onto Outsider enemies within a single campaign
Finish off 20 aliens using melee attacks within a single campaign
Use all of the agent and player abilities in the field within a single campaign
Strip all of the armor off of 5 Mutons before killing them within a single campaign
Defeat all the Outsiders before escaping on the Skyranger
Have Mind Controlled enemies get a total of 15 kills within a single campaign
Complete the first trial in Hangar 01
Trigger the Invasion in Hangar 6
Defeat the Hangar 6 R&D Invaders
Destroy 60 enemies with DaSilva's Demo Charges within a single Hangar 6 R&D campaign
Beat Hangar 6 R&D without firing any alien weapons
Take a level 5 agent of every class into the field within a single Hangar 6 R&D campaign
Complete DaSilva's perk tree without choosing Lift, Drone, or Mind Control