  We present two classes of stars with yet unknown evolutionary phase: the B[e]
supergiants and the so-called unclassified B[e] stars. While the B[e]
supergiants are luminous post-main sequence stars with high mass progenitors,
not much is known of the unclassified stars. We discuss how it might be
possible to determine their evolutionary phases in the area of new large
telescopes.
