  We present preliminary results of a long-term project to investigate the
process of accretion and tidal disruption of dSph satellites in the Galactic
halo and, in particular, to search for new tidal tails in a sample of nearby
dSph satellites of the Milky Way. Here we present our finding of extra-tidal
debris in the Ursa Minor dS ph and discuss the detection by the Sloan Digitized
Sky Survey team of what could be a tidal stream associated to the Sagittarius
dSph.

Astrophysics