I will discuss how to construct degenerations of Calabi-Yau manifolds from certain combinatorial data on integral affine manifolds with singularities. These are real manifolds which, off of some codimension two set, have an atlas whose transition functions lie in the affine linear group of Z^n. The explicit description of the degeneration is described in terms of tropical disks, i.e., trees in the affine manifold with leaves in the bad codimension two set, edges being straight lines, and vertices satisfying certain weighting conditions.