We study how newly synthesised proteins and proteins taken up from the cell surface are sorted and delivered to the appropriate destination within the cell. The correct traffic of these proteins plays a critical role in regulating cell proliferation, survival and differentiation in all cells. We also study specific traffic events in cells of the eye, focusing on retinal pigment epithelial cells (RPE). Melanin pigment within the RPE is critical for eye development and protects the adult eye from light and oxidative stress. We study how pigment granules are made, how they move and how defects in these processes contribute to inherited retinal degenerations. RPE also take up and degrade spent photoreceptor segments and a gradual build-up of undigested products within the RPE occurs with age and is increased in AMD. We study the regulation of degradation of outer segments in order to understand how these processes breakdown with age and disease.