  The perturbations of satellite galaxies, in particular the Large Magellanic
Cloud (LMC), have been repeatedly proposed and discounted as the cause of the
Milky Way warp. While the LMC may excite a wake in the Galactic dark matter
halo that could provide sufficient torque to excite a warp of the observed
magnitude, its orbit may be incompatible with the orientation of the warp's
line of nodes. The Sgr dSph galaxy has an appropriately-oriented orbit, and due
to its closer orbit may produce a stronger tidal effect than the LMC. Evidence
that Sgr may be responsible for the warp comes from its orbital angular
momentum, which has the same magnitude as the angular momentum of the warped
component of the Galactic disk and is anti-aligned with it. We have run high
resolution numerical N-body simulations of Sgr-sized satellites around a Milky
Way-sized disk to test this idea. Preliminary results suggest that Sgr-sized
satellites can indeed excite warps with properties similar to that observed for
the Milky Way.

Astrophysics