The versatile differentiation potential of adipose-derived stem cells (ASC) into cells of mesodermal, entodermal, and ectodermal origin places these cells at the forefront of cell-based therapies and cell transplantation. Epithelial differentiation of ASC may either be initiated by direct cell-cell or cell-matrix contacts, by chemical factors like retinoic acid, or via secreted cellular factors like cytokines, interleukins, or growth factors included in conditioned media.This protocol describes methods to induce the in vitro differentiation of ASC from human adipose tissue into the epithelial lineage, and describes the methods used to verify this induced differentiation. We present two differentiation protocols based on either retinoic acid or conditioned medium of cultured epithelial cells.