  Holomorphic disk invariants with boundary in the real Lagrangian of a quintic
3-fold are calculated by localization and proven mirror transforms. A careful
discussion of the underlying virtual intersection theory is included. The
generating function for the disk invariants is shown to satisfy an extension of
the Picard-Fuchs differential equations associated to the mirror quintic. The
Ooguri-Vafa multiple cover formula is used to define virtually enumerative disk
invariants. The results may also be viewed as providing a virtual enumeration
of real rational curves on the quintic.
