  Pulsations in subdwarf B (sdB) stars are an important tool to constrain the
evolutionary status of these evolved objects. Interestingly, the same data used
for this asteroseismological approach can also be used to search for substellar
companions around these objects by analyzing the timing of the pulsations by
means of a so-called O-C diagram. Substellar objects around sdB stars are
important for two different reasons: they are suspected to be able to influence
the evolution of their host-star and they are an ideal test case to examine the
properties of exoplanets which have survived the red giant expansion of their
host stars.
