Hearing aids with digital signal processing demonstrate a large dynamic range with negligible distortion and no significant inherent noise. Furthermore, many acoustic parameters allow the compensation of even severe hearing loss, and the adjustment is extremely accurate. However, the new hearing aid generation not only requires computerized fitting, but also an experienced examination with new integrated fitting procedures. In addition to in situ measurement, the hearing aid fitting should include not only the Freiburg speech test, but also the Göttingen sentence test and the monosyllable rhyme test with different noises, for example the Fastl noise or the Döring babble noise. Loudness scaling with different methods is particularly important.