Résumé: Diagnosis of hearing impairment is possible during the first days of life. Hearing tests are noninvasive and should not be delayed when hearing loss is suspected. Among children's hearing impairments, conductive hearing loss is the most frequent; it is generally acquired and reversible. At the opposite pole, sensorineural hearing loss has more severe consequences because it is irreversible and often present from birth. Early diagnosis and treatment are necessary in all cases to prevent speech delay. In cases with sensorineural hearing impairment, hearing aid fitting, or even cochlear implantation, and intensive speech therapy will help deaf children learn speech, with the view of optimal social and professional integration.