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