Saline nasal irrigation is an adjunctive therapy for upper respiratory conditions that bathes the nasal cavity with spray or liquid saline. Nasal irrigation with liquid saline is used to manage symptoms associated with chronic rhinosinusitis. Less conclusive evidence supports the use of spray and liquid saline nasal irrigation to manage symptoms of mild to moderate allergic rhinitis and acute upper respiratory tract infections. Consensus guidelines recommend saline nasal irrigation as a treatment for a variety of other conditions, including rhinitis of pregnancy and acute rhinosinusitis. Saline nasal irrigation appears safe, with no reported serious adverse events. Minor adverse effects can be avoided with technique modification and salinity adjustment.