For improving the directionality of a hearing aid having a microphone system formed by two or more microphones without in the process creating an increase in the microphone noise that the hearing aid wearer finds to be disturbing, the microphone system is adjusted statically or adaptively taking into account the individual rest hearing threshold and/or taking into account the individual masking threshold for the microphone noise that is produced by the microphone system. The greatest possible extent of directionality thus can be allowed, without the hearing aid wearer in the process finding the microphone noise that is produced by the microphone system to be disturbing.