Laboratory investigations of the ability of human and other Retinal Pigmented Epithelium cells to survive have provided guidelines for the handling and preparation of RPE from normal and pathologic eyes for culture. Rapid post-mortem enucleation and rapid cooling and storage at 4 degrees C, if immediate processing is not possible, are crucial to the regular, successful establishment of RPE cells in vitro. Cultured cells have been used to investigate the composition and biologic activity of various intraocular tissues, including the RPE by itself and in combination with other cell types. Although cultured RPE cells lack certain activities associated with RPE in vivo, they do retain a number of differentiated functions and, thus, are useful in the investigation of questions related to the promotion of differentiation, survival, fluid transport and extracellular matrix production, among others. Future refinements and improvements in culture conditions should augment the utility of these cells in vision research.