Yes, in most cases in the US, you're correct. A vast majority of hiring relationships are "at will" relationships -- which means you can leave at will and be f

Yes, in most cases in the US, you're correct. A vast majority of hiring relationships are "at will" relationships -- which means you can leave at will and be fired at will. The exceptions are when there's a formal employment contract in place -- unions do this, certain professions do this (professors, etc.), and certain executive packages are under contract as well. But in general, yes, you can quit on a moment's notice and be fired on the same. NOW - most "smart" companies won't just do this. A good manager wants his/her employees to succeed, and if something isn't going right, they'll do their best to coach, warm, and help the employee improve. Are there lots of bad managers who keep it all bottled up inside until one day, boom, you're fired? Sure. It stinks. I'd like to believe there are more good managers than bad ones (at least in terms of coaching employees toward longevity.)