The effects of growth factors on re-epithelialization of wounded human and bovine corneas were studied in a simple organ culture system. Excisional trephine and epithelial scrape wounds were created on bovine and human corneo-scleral rings in which the endothelial corneal concavity was then filled with an agar-collagen mixture. Organ culture was undertaken at 37°C in a humidified 5% CO2 incubator with serum-free Medium 199 maintained at the level of the conjunctival epithelium. Rates of re-epithelialization in response to addition of exogenous epidermal growth factor (EGF), basic fibroblast growth factor (bFGF) and transforming growth factor type β1 (TGF-β1) were assessed by image analysis. Corneal cultures could be maintained for up to 3 weeks without significant stromal oedema or keratocyte deterioration and with little loss of epithelial architecture. Following wounding the cornea re-epithelialized in a similar fashion to that observed in vivo i.e. a lag phase followed by migration/proliferation and the reformation of an intact multilayered epithelium. EGF accelerated, basic FGF had no effect on, and TGF-β1 inhibited the rate of corneal re-epithelialization. Our organ culture model maintains corneal integrity and provides a practical system in which to study factors that modulate corneal re-epithelialization following wounding.