  I review the AdS/hydrodynamics correspondence, which provides a 1-1 map
between large wavelength features of AdS black branes and conformal fluid
flows. In this thesis I consider boundaries between nonrelativistic flows,
applying the usual boundary conditions for viscous fluids. I find that a naive
application of the correspondence to these boundaries yields a surface layer in
the gravity theory whose stress tensor is not equal to that given by the Israel
matching conditions. In particular, while neither stress tensor satisfies the
null energy condition and both have nonvanishing momentum, only Israel's tensor
has stress. The disagreement arises entirely from corrections to the metric due
to multiple derivatives of the flow velocity, which violate Israel's finiteness
assumption in the thin wall limit.
