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