To summarize the current state of cochlear implantation in children.Hearing loss profoundly impacts a child's ability to communicate and thereby affects educational and psychosocial development. The auditory cortex has sensitive periods during which it is maximally receptive to sound stimulus and consequent development. For this reason, there is impetus to implant children at a very young age, as a cochlear implant can provide auditory input during this critical window. Long-term follow-up of implanted children has shown that cochlear implants are able to provide substantial language, academic, and social benefit. The criteria for cochlear implantation have broadened, and promising outcomes are being seen in populations that were not previously considered for implantation. The best language acquisition outcomes are seen in recipients who were implanted at a younger age and are in an environment rich in oral communication. Bilateral implantation offers some acoustic advantages.Cochlear implants provide sound perception to deaf children and can mitigate, to varying extents, the effects of sound deprivation on auditory development. On the basis of our understanding of brain development and language outcomes, a wider population of children are now candidates for implantation than previously considered.