  Subdwarf B (sdB) stars form the blue end of the horizonal branch. Their
peculiar atmospheric abundance patterns are due to diffusion processes.
However, diffusion models fail to explain these anomalies quantitatively. From
a NLTE model atmosphere analysis of 40 sdB stars, we found that the more
luminous (i.e. more evolved) stars have anomalous H alpha and HeI 6678Ang line
profiles, i.e, the lines are too broad and shallow and may even show some
emission. We interpret these anomalies as the signatures of a stellar wind, the
first such detection in this class of star (if confirmed). Mass loss may also
explain the peculiar abundance patterns seen in sdB stars. High-quality UV
spectra are needed to confirm that these stars do have stellar winds.
