  We consider spherically symmetric gravity coupled to a spherically symmetric
scalar field with a specific coupling which depends on the Areal Radius.
Classical collapse is described by the Vaidya solution. The semiclassical
Einstein equations are well defined. Their solution describes an evaporating
black hole. A balance law at future null infinity relates the rate of change of
a back reaction-corrected Bondi mass to a manifestly positive flux. Its
detailed form suggests a quantum extension of future null infinity along which
all information including that in the collapsing matter is expected to emerge.
