  I review the up-to-date status on the properties of the Dark Matter density
distribution around Galaxies. The rotation curves of spirals all conform to a
same Universal profile which can be uniquely decomposed as the sum of an
exponential thin stellar disk and a dark halo with a flat density core.
  From dwarfs to giants galaxies, the halos embedding the stellar component
feature a constant density region of size $r_0$ and value $\rho_0$, which are
inversely correlated. The fine structure of dark halos in the region of the
stellar disk has been derived for a number of low--luminosity disk galaxies:
the halo circular velocity increases almost linearly with radius out to the
edge of the stellar disk, implying, up there, an almost constant dark matter
density. This sets a serious discrepancy between the cuspy density distribution
predicted by N-body simulations of $\Lambda$CDM cosmology, and those actually
detected around galaxies. The small scatter around the Fundamental Plane (FP)
of elliptical galaxies constraints the distribution of dark and luminous matter
in these systems. The measured central velocity dispersion $\sigma_0$ in the FP
is linked to both photometric and dynamical properties of luminous and dark
matter. As a consequence, the well-known features of the FP imply that, inside
the effective radius $R_e$, the stellar spheroid must dominate over the dark
matter, in contrast with $\Lambda$CDM predictions.
