  New high resolution spectroscopic and medium resolution spectropolarimetric
data, complemented with optical broad and narrow band imaging, of the B[e] star
HD 87643 are presented. The spectrum of HD 87643 exhibits the hybrid
characteristics well known to be representative of the group of B[e] stars; a
fast wind with an expansion velocity in excess of 1000 km/s is measured in the
hydrogen and helium lines, while a slower component is traced by lower
excitation lines and forbidden lines. Clues to the geometry of the rapidly
expanding circumstellar shell are provided by the startling polarization
changes across Halpha. Comparison with published schematic calculations
indicates that the polarizing material is located in a slowly rotating,
expanding disk structure. A hydrodynamical model is then presented whose
results are consistent with the original two-wind concept for B[e] stars and
exhibits kinematic properties that may well explain the observed spectral
features in HD 87643. The model calculations use as input a B star undergoing
mass loss, surrounded by an optically thick disk. The resulting configuration
consists of a fast polar wind from the star and a slowly expanding disk wind.
The model also predicts that the stellar wind at intermediate latitudes is
slower and denser than in the polar region.
