Severe acute respiratory syndrome (SARS) is caused by the SARS coronavirus (SCV). The disease appeared in the Guandong province of southern China in 2002. The epidemic affected > 8422 patients and caused 908 deaths in 29 countries on 5 continents. Several treatment modalities were tried with limited success to treat SARS and a variety of experimental drugs are under development. Type I interferons (IFNs-alpha/beta) were suggested as potential candidates to treat SARS. Several animal and human coronaviruses, including SCV, were shown to be sensitive to IFNs both in vitro and in vivo. A pilot clinical report showed effectiveness of IFN-alpha for the treatment of SARS patients. This review summarises antiviral activities of IFNs with special regard to SARS, and reviews the published clinical and experimental data describing the use of IFNs for SARS.