  Studies of high resolution quasar absorption lines (QALs), arising from gas
in local and z < 1.5 galaxies, provide direct probes of the kinematic,
chemical, and ionization conditions and evolution of Milky Way-like galaxies.
Inferences drawn from these studies provide a powerful analog for those based
upon direct studies of the Halo. The observed gas kinematics and velocity
evolution reveal that galactic halos are complex dynamical components,
consistent with Searle--Zinn formation scenarios.

Astrophysics