  We present the results of a galaxy redshift survey in the central region of
the Shapley Concentration. Our total sample contains ~2000 radial velocities of
galaxies both in the clusters and in the intercluster field.
  We reconstruct the density profile of this supercluster, calculate its
overdensity and total mass. Moreover we detect a massive structure behind the
Shapley Concentration, at ~30000 km/s.
