Abstract: In a process for operating a speech dialog system, which adapts its to the speech quality of different speakers, the speech recognizer estimates the probability of a correct recognition of the user response or expression, in that it consults for estimation a confidence gage by means of which the words or phrases potentially contained in the speech response or expression are assigned a confidence value. One of the particularly preferred solutions of the inventive task are comprised in that for those speakers which are difficult for the speech dialog system to understand, it accepts in certain cases repetitions of the same user responses which, by themselves, would not be acceptable. A further advantageous solution is comprised therein, that the confidence threshold is selected depending upon the actual current dialog step.