Please make sure you have REALLY received truly bad service before complaining to management to have automatic gratuities removed or adjusted. Your server will not only lose their gratuity, but will have disciplinary action, including record card reprimands which can lead to termination. And again, I agree the time to complain to management is not when the bill is presented, or later. It is, as the above poster suggested, right when you are displeased with your service--it should then improve, and your dining experience will be so much better. And isn't that the point?