The extent that status epilepticus (SE), but also brief seizures, affects neuronal structure and function has been the subject of much clinical and experimental research. There is a reliance on findings from animal research because there have been few prospective clinical studies. This review suggests that the features of seizure-induced injury in the immature brain compared with the adult brain are different and that duration of seizures (SE versus brief), number of seizures, cause of seizures, presence of pre-existing abnormalities, and genetics affect the injury. Increased awareness of age-specific injuries from seizure has promoted research to determine the circumstances under which seizures may produce permanent detrimental effects. Together with recent advances in functional neuroimaging, genomic investigation, and prospective human data, these studies are likely to substantially increase our knowledge of seizure-induced injury, leading to the development of improved algorithms for prevention and treatment of epilepsy.