More than 30 million U.S. adults have hearing loss. This condition is underrecognized, and hearing aids and other hearing enhancement technologies are underused. Hearing loss is categorized as conductive, sensorineural, or mixed. Age-related sensorineural hearing loss (i.e., presbycusis) is the most common type in adults. Several approaches can be used to screen for hearing loss, but the benefits of screening are uncertain. Patients may present with self-recognized hearing loss, or family members may observe behaviors (e.g., difficulty understanding conversations, increasing television volume) that suggest hearing loss. Patients with suspected hearing loss should undergo in-office hearing tests such as the whispered voice test or audiometry. Patients should then undergo examination for cerumen impaction, exostoses, and other abnormalities of the external canal and tympanic membrane, in addition to a neurologic examination. Sudden sensorineural hearing loss (loss of 30 dB or more within 72 hours) requires prompt otolaryngology referral. Laboratory evaluation is not indicated unless systemic illness is suspected. Computed tomography or magnetic resonance imaging is indicated in patients with asymmetrical hearing loss or sudden sensorineural hearing loss, and when ossicular chain damage is suspected. Treating cerumen impaction with irrigation or curettage is potentially curative. Other aspects of treatment include auditory rehabilitation, education, and eliminating or reducing use of ototoxic medications. Patients with sensorineural hearing loss should be referred to an audiologist for consideration of hearing aids. Patients with conductive hearing loss or sensorineural loss that does not improve with hearing aids should be referred to an otolaryngologist. Cochlear implants can be helpful for those with refractory or severe hearing loss.