TEMPEST is a U.S. National Security Agency specification and a NATO certification referring to spying on information systems through leaking emanations, including unintentional radio or electrical signals, sounds, and vibrations.

The traditional approach for TEMPEST product approval provides for government supervision of evaluations to include testing oversight and technical reviews of both the TEMPEST test plans and test reports produced by a nation’s TEMPEST evaluation personnel.

NATO agreed on a scheme in 1981 to have vendors offer approved TEMPEST products for sale to NATO and NATO member nations.