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Results from SLC and LEP indicate that there are only three
generations of leptons[55] within the standard gauge theory of
electromagnetic and weak interactions[56]. The heaviest of these
leptons, the 
, serves as an excellent laboratory for studying many
aspects of the Standard Model[57]. Of all the known leptons only the
is massive enough to decay into both purely leptonic states and
semileptonic states with accompanying hadrons. The purely leptonic decays
allow the study of lepton universality and the 
vertex,
while the semileptonic decays permit the investigation of the weak hadronic
current and strong interaction effects. The decay of the allows
the measuring of the 
mass and the search for
Standard Model forbidden decays involving three generations of leptons with or
without accompanying hadrons.
To date all meaningful studies of the properties of the have been
carried out at e
e
colliders. At these facilities the cross section for
production is relatively large while the associated backgrounds are
both calculable and small. These advantages suggest that ee colliders
will be the place to measure the decay characteristics of the for many
years to come. For CLEO III we assume an integrated
luminosity of 30 fb
for which there will be about 27 million
pairs produced. In Table 
we list the data samples which
will be available for various decays. In this section, we
discuss a selected sample of physics topics that can be studied at an upgraded
CESR/CLEO facility. We will assume that the one-charged-particle decay
discrepancy has been resolved and thus will not be discussed here.
