Aeromonas hydrophila was isolated from the eye swabs of four patients. Two were thought to have definite clinical infection; one had chronic conjunctivitis complicating the wearing of contact lenses, and the other had acute conjunctivitis associated with ectropion and lacrimal duct stenosis. Two patients had no clinical evidence of infection. Both of them had swabs taken at the time of surgery. One had a cataract extraction and the other had a lensectomy and vitrectomy for a penetrating injury. The outcome was satisfactory in the two patients in whom colonization occurred, and in the patient with acute conjunctivitis, all of whom received chloramphenicol with or without gentamicin. The fourth patient was not followed up.