  We consider aspects of holography in the $pp$-wave limit of $AdS_5\times S5$.
This geometry contains two $\RR4$'s, one obtained from $AdS_5$ directions, and
the other from the $S 5$. We argue that the holographic direction in the
$pp$-wave background can be taken to be $r$, the radial direction in the first
$\RR4 $. Normalizable modes correspond to states, and non-normalizable modes
correspond to deformations of the boundary theory. In the strict $pp$-wave
limit, there are additional non-normalizable modes in the second $\RR 4$, which
have no apparent super-Yang-Mills interpretation. We outline the procedure for
calculating correlation functions holographically.
