The goal of this article is to show that, if one avoids star forming r
egions, mass-losing AGB stars can generally be selected from the data
that will be provided by the near-infrared surveys which are presently
considered. Also, if IRAS data are available, the separation between
carbon-rich and oxygen-rich stars can be operated by their positions i
n infrared colour diagrams. In extragalactic systems, red supergiants
can be discriminated from AGB stars by their luminosities.