  This contribution will survey recent progress toward an understanding of
diverse pairing phenomena in dilute nuclear matter at small and moderate
isospin asymmetry, with results of potential relevance to supernova envelopes
and proto-neutron stars. Application of {\it ab initio} many-body techniques
has revealed a rich array of temperature-density phase diagrams, indexed by
isospin asymmetry, which feature both conventional and unconventional
superfluid phases. At low density there exist a homogeneous translationally
invariant BCS phase, a homogeneous LOFF phase violating translational
invariance, and an inhomogeneous translationally invariant phase-separated BCS
phase. The transition from the BCS to the BEC phases is characterized in terms
of the evolution, from weak to strong coupling, of the pairing gap, condensate
wave function, and quasiparticle occupation numbers and spectra. Additionally,
a schematic formal analysis of pairing in neutron matter at low to moderate
densities is presented that establishes conditions for the emergence of both
conventional and unconventional pairing solutions and encompasses the
possibility of dineutron formation.
