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