The retinal pigment epithelium (RPE) is a cellular monolayer between the choriocapillaris and the photoreceptors which controls the uptake of nutrients by the retina and the disposal of shed photoreceptor outer segments from the retina. The RPE is responsible for a continuous supply of rhodopsin by the retinol cycle and blocking of light by its pigmentation to minimize light-induced oxidation of retinal lipids and proteins. Proteins encoded by genes in which mutations are responsible for hereditary disorders of the retina and the RPE are involved in all these functions. In this article these genes and disorders are reviewed in the context of a functional network.