Hot subdwarf stars are particularly challenging for asteroseismology due to
their rapid pulsation periods, intrinsic faintness and relative rarity both in
the field and in clusters. These features have ensured that the preferred
method of observation up to now has been white-light photometry, and all
asteroseismological solutions to date have been made by model fitting of the
frequency spectrum. Several attempts have been made to perform asteroseismology
using time-resolved spectroscopy on the brightest of these stars, but with
modest results. A few attempts at simultaneous multi-color photometry have also
been made to identify modes with the amplitude ratio method. We will review the
most recent observational results and progress in improving the observational
methods for ground-based asteroseismology of these compact pulsators.Comment: 8 pages, to appear in Astronomische Nachrichten, Vol. 331, 102