Influenza viruses cause annual epidemics in the United States. Although the severity of influenza epidemics vary by season, the morbidity associated with annual influenza epidemics in children is considerable from year to year. Excess pediatric outpatient clinic visits, emergency department visits, hospitalizations, and deaths occur each influenza season and are more common among younger children and those with conditions that increase their risk for developing influenza-related complications. Vaccination is the most effective way to prevent influenza and its complications and is recommended for all children 6 months through 18 years of age. Antiviral treatment is another tool to prevent influenza and reduce the duration of illness and complications. This article will review the virological, clinical, and epidemiological features of seasonal influenza, as well as discuss seasonal influenza vaccination and antiviral therapy.