Here is the full list of all 42 Gunpoint achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Tell Gessler that Rooke's hired you to betray him.
Create a custom mission with at least one objective.
Complete a mission faster than I can.
Publish your personalised epilogue.
Notice the story doesn't necessarily gel with the mechanics. Become qualified games journalist.
Complete the game.
Knock Fritz Gessler out of his office window.
Slam Fritz Gessler's office door into him.
Kick Fritz Gessler's office door into him.
Shoot Fritz Gessler.
Beat Fritz Gessler to death.
Knock Fritz Gessler out with a punch.
Intimidate Fritz Gessler into surrendering.
Defeat Gessler by rewiring his gun.
Catch a guilty man at the expense of freeing an innocent one.
Mock the chief of police at a critical moment.
Use the Gatecrashers to kick a door through a window.
Use the Gatecrashers to kick a door into a guard.
Use the Gatecrashers to kick a door off its hinges.
Free an innocent man at the expense of catching a guilty one.
This is an achievement in name only. No-one admires you for punching a guy that many times.
Chicken out of telling Katie the truth at the last minute.
Help justify my early, not entirely wise choice of game name by holding someone at gunpoint with the Resolver.
Use the Longshot to make a guard unintentionally shoot another (outside of the test lab).
Use the Prankspasm to knock out someone who isn't standing near a power socket (outside of the test lab).
Jump into an Enforcer to knock him through a window.
Steal Gessler's technology for Rooke.
Use the Hushcracker to jump through a window silently (outside of the test lab).
Upgrade your battery capacity to the non-figurative max.
Complete the police chief's missions without incriminating yourself.
Upgrade your Bullfrog Hypertrousers to pounce instantly.
Upgrade your Bullfrog Hypertrousers to maximum jump strength.
Use the Dropshot to land silently from a great height.
Conceal your presence at the DataSec break-in from Mayfield.
Complete a mission that has guards with no violence, witnesses or loud noises.
Voluntarily tell Katie the truth.
Use no violence at all on a mission that has guards.
Get knocked down by an opening door.
Use the Crosslink to create an infinite loop that burns itself out.
Leave no living witnesses to your presence on a mission that has guards.
Knock a guard out by opening a door into him.
Wire an elevator button to trigger something when the elevator arrives.