  The origin of chemically peculiar stars remains enigmatic, especially
regarding their frequency among their "normal" peers. In addition to magnetic
fields and rotation, multiplicity may shed light on the question. We mention
the main surveys of the three kinds performed so far of intermediate mass
stars, either normal or chemically peculiar, magnetic or not: imaging,
spectroscopic, and photometric. We also consider the mulitiplicity of red giant
stars, since many of them are descendants of A-type stars, through Mermilliod's
radial velocity monitoring of open cluster members. We briefly review the
orbital properties of binary systems hosting chemically peculiar stars. Some
specific objects of special interest are mentioned as deserving further study.
Finally, we recall that some binary systems composed of A-type stars are
progenitors of Type Ia supernovae, and evoke the potentialities of future
surveys like Gaia.
