Full thickness eyewall explants were made from human eyes, the retina and retinal pigment epithelium were removed, and the explants were maintained in vitro in Ham's F-10 medium with 20% foetal bovine serum. Cultured explants were examined by scanning and transmission electronmicroscopy after varying lengths of time. When in vitro, choroidal cells migrated across the cut edge of the explant onto the denuded Bruch's membrane where they subsequently showed production of extracellular matrix. In the human eye, ingrowth of choroidal cells on Bruch's membrane is found in macular degenerations, inflammatory chorioretinal disorders and subsequent to trauma. The in vitro model system presented in our study could facilitate evaluation of the dynamics underlying such ingrowth and also of factors affecting the course of this process.