  We perform a comprehensive analysis of the Minimal Supersymmetric Standard
Model (MSSM) in the scenario where the scalar partners of the fermions and the
Higgs particles (except for the Standard-Model-like one) are assumed to be very
heavy and are removed from the low-energy spectrum. We first summarize our
determination of the mass spectrum, in which we include the one-loop radiative
corrections and resum to all orders the leading logarithms of the large scalar
masses, and describe the implementation of these features in the FORTRAN code
SuSpect which calculates the masses and couplings of the MSSM particles. We
then study in detail the phenomenology of the model in scenarios where the
gaugino mass parameters are non-universal at the GUT scale, which leads to very
interesting features that are not present in the widely studied case of
universal gaugino mass parameters. We discuss the constraints from collider
searches and high-precision measurements, the cosmological constraints on the
relic abundance of the neutralino candidate for the Dark Matter in the Universe
- where new and interesting channels for neutralino annihilation appear - and
the gluino lifetime. We then analyze, in the case of non-universal gaugino
masses, the decays of the Higgs boson (in particular decays into and
contributions of SUSY particles), of charginos and neutralinos (in particular
decays into Higgs bosons and photons) and of gluinos, and highlight the
differences from the case of universal gaugino masses.
