Operation in defined airspace with reduced vertical separation minima (RVSM)

An operator shall not operate an aeroplane in defined portions of airspace where, based on regional air navigation agree- ment, a vertical separation minimum of 300 m (1 000 ft) applies unless approved to do so by the Authority (RVSM Approval).

Source: EU-OPS

See also:
Equipment for operation in defined airspace with reduced vertical separation minima (RVSM)
Operation in defined airspace with reduced vertical separation minima (RVSM)