  Muon colliders and neutrino factories are attractive options for future
facilities aimed at achieving the highest lepton-antilepton collision energies
and precision measurements of Higgs boson and neutrino mixing matrix
parameters. The facility performance and cost depend on how well a beam of
muons can be cooled. Recent progress in muon cooling design studies and
prototype tests nourishes the hope that such facilities could be built starting
in the coming decade. The status of the key technologies and their various
demonstration experiments is summarized. Prospects "post-P5" are also
discussed.
