  We investigate the properties of satellite galaxies formed in N-body/SPH
simulations of galaxy formation in the $\Lambda$CDM cosmology. The simulations
include the main physical effects thought to be important in galaxy formation
and, in several cases, produce realistic spiral discs. In total, a sample of 9
galaxies of luminosity comparable to the Milky Way was obtained. At magnitudes
brighter than the resolution limit, $M_V=-12$, the luminosity function of the
satellite galaxies in the simulations is in excellent agreement with data for
the Local Group. The radial number density profile of the model satellites, as
well as their gas fractions also match observations very well. In agreement
with previous N-body studies, we find that the satellites tend to be
distributed in highly flattened configurations whose major axis is aligned with
the major axis of the (generally triaxial) dark halo. In 2 out of 3 systems
with sufficiently large satellite populations, the satellite system is nearly
perpendicular to the plane of the galactic disc, a configuration analogous to
that observed in the Milk Way. The discs themselves are perpendicular to the
minor axis of their host halos in the inner parts, and the correlation between
the orientation of the galaxy and the shape of the halo persists even out to
the virial radius. However, in one case the disc's minor axis ends up, at the
virial radius, perpendicular to the minor axis of the halo. The angular momenta
of the galaxies and their host halo tend to be well aligned.
