  The properties of radio galaxies and quasars with and without optical or
X-ray jets are compared. The majority of jets from which high-frequency
emission has been detected so far (13 with optical emission, 11 with X-rays, 13
with both) are associated with the most powerful radio sources at any given
redshift. It is found that optical/X-ray jet sources are more strongly beamed
than the average population of extragalactic radio sources. This suggests that
the detection or non-detection of optical emission from jets has so far been
dominated by surface brightness selection effects, not by jet physics. It
implies that optical jets are much more common than is currently appreciated.
