  The DENIS $IJK$ survey of the entire southern sky is beginning observations
this year. It will return one million images, representing 4 Terabytes, among
which nearly $10^8$ stars and up to one million galaxies. The main
extragalactic applications of such a multi-band, digital, near-IR 2D survey are
listed, and the importance and feasibility of a spectroscopic followup are
discussed. First estimates of the capabilities for galaxy extraction are given,
and illustrated with preliminary images of three very bright galaxies.
