  We characterize the geometry produced by M5-branes wrapping a Special
Lagrangian 3-cycle in a Calabi-Yau 3-fold. The presence of the brane replaces
the the Calabi-Yau by a real manifold with an almost complex structure. We show
that, in this classification, a distinguished (1,1) form as well as a globally
defined (3,0) form play an important role. The requirements of supersymmetry
preservation impose constraints on these structures which can be used to
classify the background.
