  A new gauge driver is introduced for the generalized harmonic (GH)
representation of Einstein's equation. This new driver allows a rather general
class of gauge conditions to be implemented in a way that maintains the
hyperbolicity of the combined evolution system. This driver is more stable and
effective, and unlike previous drivers, allows stable evolutions using the
dual-frame evolution technique. Appropriate boundary conditions for this new
gauge driver are constructed, and a new boundary condition for the ``gauge''
components of the spacetime metric in the GH Einstein system is introduced. The
stability and effectiveness of this new gauge driver are demonstrated through
numerical tests, which impose a new damped-wave gauge condition on the
evolutions of single black-hole spacetimes.
