[en] An optical linear polarization map is presented for the bipolar nebula M2-9. The map shows a centro-symmetric pattern characteristic of a nebula illuminated by an embedded central source, and reveals the presence of a dust shell around the source. The central object itself is found to be extended along the minor axis of the nebula. Light received from a bright condensation within the dust shell is polarized by grains in the shell that appear to be aligned either by the Davis-Greenstein mechanism or by the process proposed by Harwit. (author)