Although a concerto is usually a piece of music for one or more solo instruments accompanied by a full orchestra, several composers have written works with the apparently contradictory title Concerto for Orchestra. This title is usually chosen to emphasise soloistic and virtuosic treatment of various individual instruments or sections in the orchestra, with emphasis on instruments changing during the piece. It differs from sinfonia concertante in that it has no soloist or group of soloists that remains the same throughout the composition.