  We have studied the correlation among X-ray absorption, optical reddening and
nuclear dust morphology in Seyfert 2 galaxies. Two main conclusions emerge: a)
the Balmer decrement and the amount of X-ray absorption are anticorrelated on a
wide range of column density: 10^{21} < N_H < 10^{24} atoms/cm/cm. The
correlation does no longer apply to Compton-thick objects (N_H < 10^{24}
atoms/cm/cm), although they span a comparable range in Balmer decrement; b)
Compton-thin Seyfert 2s seem to prefer nuclear environments, which are rich of
dust on scales of the hundreds parsecs. On the other hand, Compton-thick
Seyferts exhibit indifferently ``dust-poor'' and ``dust-rich'' environments.
These results support an extension of the Seyfert unification scenario (as
recently proposed by Matt, 2000), where Compton-thick Seyfert 2s are observed
through compact ``torii'', whereas Compton-thin ones are obscured by dust on
much larger scales
