The retinal pigment epithelium (RPE) works with the rod and cone photoreceptors of the eye to form a functional visual transduction unit. RPE death and dysfunction in age-related macular degeneration (AMD) leads to death of the photoreceptors and loss of vision. AMD is the leading cause of blindness in elderly people in the western world, yet there is currently no cure. Recent studies have shown that autologous transplantations of peripheral RPE to the macula of AMD patients is beneficial. Our lab has derived RPE from human embryonic stem cells (hESC) and induced pluripotent stem cells (iPS), providing a potential source of RPE for transplant. We have focused on characterizing the gene expression, protein expression and cellular function of these stem cell derived RPE. We have also looked at the stability of these cells over multiple passages. Stem cell derived RPE are highly similar to human fetal RPE at low passages, but by passage 5 have changed morphology and gene expression dramatically, resulting in a loss of cellular function. These studies demonstrate that stem cell-RPE is a promising cellular therapy for AMD, although the challenge of scalability still needs to be solved.