  Oe stars are a subset of the O-type stars that exhibit emission lines from a
circumstellar disk. The recent detection of magnetic fields in some O-type
stars suggests a possible explanation for the stability of disk-like structures
around Oe stars. According to this hypothesis, the wind of the star is
channeled by a dipolar magnetic field producing a disc in the magnetic
equatorial plane. As a test of this model, we have obtained spectropolarimetric
observations of the hottest Galactic Oe star HD 155806. Here we discuss the
results and implications of those observations.
