  Using the StarTrack population synthesis code we analyze the formation
channels possibly available to double neutron star binaries and find that they
can be richer than previously thought. We identify a group of short lived,
tight binaries, which do not live long enough to escape their host galaxies,
despite their large center-of-mass velocities. We present our most recent
results on all possible evolutionary paths leading to the formation of double
neutron stars, calculate their coalescence rates, and also revisit the question
of the distribution of merger sites around host galaxies. For a wide variety of
binary evolution models and galaxy potentials, we find that most of neutron
star mergers take place within galaxies. Our results stem from allowing for
radial and common envelope evolution of helium-rich stars (testable in the
future with detailed stellar-structure and hydrodynamic calculations) and
indicate that double neutron star binaries may not be excluded as Gamma-Ray
Burst (GRB) progenitors solely on the basis of their spatial distribution
around host galaxies. We also find, in contrast to Bethe & Brown (1998), that
in a significant fraction of common envelope (CE) phases neutron stars do not
accrete enough material to become black holes, and thus the channels involving
CEs are still open for the formation of double neutron stars.
