  We study the formation and stability of regular black holes by employing a
thin shell approximation to the dynamics of collapsing magnetic monopoles. The
core deSitter region of the monopole is matched across the shell to a
Reissner-Nordstrom exterior. We find static configurations which are
nonsingular black holes and also oscillatory trajectories about these static
points that share the same causal structure. In these spacetimes the shell is
always hidden behind the black hole horizon. We also find shell trajectories
that pass through the asymptotically flat region and model collapse of a
monopole to form a regular black hole. In addition there are trajectories in
which the deSitter core encompasses a deSitter horizon and hence undergoes
topological inflation. However, these always yield singular black holes and
never have the shell passing through the aymptotically flat region. Although
the regular black hole spacetimes satisfy the strong energy condition, they
avoid the singularity theorems by failing to satisfy the genericity condition
on the Riemann tensor. The regular black holes undergo a change in spatial
topology in accordance with a theorem of Borde's.
