  Bounds for the Castelnuovo-Mumford regularity of Ext modules, over a
polynomial ring over a field, are given in terms of the initial degrees,
Castelnuovo-Mumford regularities and number of generators of the two graded
modules involved. These general bounds are refined in the case the second
module is the ring. Other estimates, for instance on the size of graded pieces
of these modules, are given. We also derive a bound on the homological degree
in terms of the Castelnuovo-Mumford regularity. This answers positively a
question raised by Vasconcelos.
