  The properties of bright extragalactic planetary nebulae are reviewed based
upon the results of low and high resolution spectroscopy. It is argued that
bright extragalactic planetary nebulae from galaxies (or subsystems) with and
without star formation have different distributions of central star temperature
and ionization structure. As regards the chemical compositions, oxygen and neon
are generally found to be unchanged as a result of the evolution of the stellar
progenitors. Nitrogen enrichment may occur as a result of the evolution of the
progenitors of bright planetary nebulae in all stellar populations, though this
enrichment may be (more) random in old stellar populations. Helium abundances
appear to be influenced by the chemical evolution of the host galaxy, with
planetary nebulae in dwarf spheroidals having systematically elevated
abundances. Neither the age nor the metallicity of the progenitor stellar
population has a strong effect upon the kinematics observed for nebular shells.
Both the range of expansion velocites, 8-28 km/s, and the typical expansion
velocity, ~18 km/s, are found to be relatively constant in all galaxies. On the
other hand, bright planetary nebulae in the bulge of M31 have systematically
higher expansion velocities than their counterparts in M31's disk. The
expansion velocities show no trend with nebular Hbeta luminosity, apart from a
lack of large expansion velocities at the highest luminosities (the youngest
objects), but appear to correlate with the 5007/Hbeta ratio, at least until
this ratio saturates. These results suggest a link between the evolution of the
nebular shells and central stars of bright extragalactic planetary nebulae.
