  Distant planetary nebulae (PNe) are used to measure distances through the PN
luminosity function, as kinematic tracers in determining the mass distribution
in elliptical galaxies, and most recently, for measuring the kinematics of the
diffuse stellar population in galaxy clusters. This article reviews the
photometric and spectroscopic survey techniques that have been used to detect
PNe beyond the Local Group, out to the Coma cluster at 100 Mpc distance.
Contaminations by other emission sources and ways to overcome them will be
discussed as well as some science highlights and future perspectives.
