  We have observed a sample of 157 Seyfert galaxies with a 275 km baseline
radio interferometer to search for compact, high brightness temperature radio
emission from the active nucleus. We obtain the surprising result that compact
radio cores are much more common in Seyfert 2 than in Seyfert 1 galaxies, which
at first seems to be inconsistent with orientation unification schemes. We
propose a model, involving optical depth effects in the narrow-line region,
which can reconcile our result with the standard unified scheme. (Accepted for
publication in ApJ 1994 Sep 10)
