  We discuss recent results on the heavy fermion superconductor CeRhIn$_5$
which presents ideal conditions to study the strong coupling between the
suppression of antiferromagnetic order and the appearance of unconventional
superconductivity. The appearance of superconductivity as function of pressure
is strongly connected to the suppression of the magnetic order. Under magnetic
field, the re-entrance of magnetic order inside the superconducting state shows
that antiferromagnetism nucleates in the vortex cores. The suppression of
antiferromagnetism in CeRhIn$_5$ by Sn doping is compared to that under
hydrostatic pressure.
