  We describe the status of our effort to realize a first neutrino factory and
the progress made in understanding the problems associated with the collection
and cooling of muons towards that end. We summarize the physics that can be
done with neutrino factories as well as with intense cold beams of muons. The
physics potential of muon colliders is reviewed, both as Higgs Factories and
compact high energy lepton colliders. The status and timescale of our research
and development effort is reviewed as well as the latest designs in cooling
channels including the promise of ring coolers in achieving longitudinal and
transverse cooling simultaneously. We detail the efforts being made to mount an
international cooling experiment to demonstrate the ionization cooling of
muons.
