Here is the full list of all 37 THIEF achievements worth 1,000 gamerscore. It takes around 40-50 hours to unlock all of the achievements on Xbox One.
Used 40,000 gold
Picked a pocket and a lock using the focus ability
Finished the game with a custom difficulty of 700 points or more
Finished the game without a single kill or knockout
Finished the game on Master difficulty
Reached the final chapter without using the focus ability
Shot a bottle in mid-air with an arrow
Finished Chapter Eight
Finished the game in 15 hours or more
Picked 100 pockets in a single playthrough
Finished Chapter Seven
Stole all loot and collectibles in a single chapter.
Completed a collectible set
Uncovered Lyegrove's secret
Completed all Client Jobs in The City
Completed all Basso Jobs in The City
Finished Chapter Six
Finished Chapter Five
Disarmed ten trap mechanisms
Finished Chapter Four
Completed 10 optional Thieving Objectives
Picked a lock with masterful speed
Finished Chapter Three
Killed or knocked out 10 people using the environment
Discovered 15 secret areas
Finished 3 consecutive chapters without taking damage
Finished Chapter Two
Sweet sixteen. Snuff said.
Stole 5 collectibles
Finished a single chapter without alerting anyone
Finished Chapter One
Finished the Prologue
Complete 25 optional Thieving Objectives
Score an epic 5,000,000 or more in a Challenge Map
Complete all collectible sets
Discover all secret areas
Find all the secret stashes in Moira