  Direct detection experiments for neutralino dark matter in the Milky Way are
examined within the framework of SUGRA models with R-parity invariance and
grand unification at the GUT scale, M_G. Models of this type apply to a large
number of phenomena, and all existing bounds on the SUSY parameter space due to
current experimental constraints are included. For models with universal soft
breaking at M_G (mSUGRA), the Higgs mass and b\to s\gamma constraints imply
that the gaugino mass, m_{1/2}, obeys m_{1/2} >(300-400)GeV putting most of the
parameter space in the co-annihilation domain where there is a relatively
narrow band in the m_0 - m_{1/2} plane. For $\mu > 0$ we find that the
neutralino -proton cross section >~ 10^{-10} pb for m_{1/2} < 1 TeV, making
almost all of this parameter space accessible to future planned detectors. For
\mu < 0, however, there will be large regions of parameter space with cross
sections < 10^{-12} pb, and hence unaccessible experimentally. If, however, the
muon magnetic moment anomaly is confirmed, then \mu >0 and m_{1/2}<~ 800 GeV.
Models with non-universal soft breaking in the third generation and Higgs
sector can allow for new effects arising from additional early universe
annihilation through the Z-channel pole. Here cross sections that will be
accessible in the near future to the next generation of detectors can arise,
and can even rise to the large values implied by the DAMA data. Thus dark
matter detectors have the possibility of studying the the post-GUT physics that
control the patterns of soft breaking.
