  In this contribution we present the results of the application of the
bisector of the cross-correlation function as a diagnostic of activity-related
radial-velocity variations. The results show that the technique is very
effective. We present examples for which the application of the bisector
analysis was essential to establish the planetary nature of the candidate or to
exclude an orbital signature. An analysis of the behaviour of the bisector for
active dwarfs of different spectral types shows that the relation between the
bisector and the radial-velocity variation depends in a great extent on the v
sin(i) of the star. The results may shed a new light on the intrinsic sources
of radial-velocity variation for different types of solar-type dwarfs.
