Bacterial keratitis is an opportunistic infection of the avascular corneal stroma, initiated by a breakdown of the epithelial barrier. Corneal abrasion with infected material, extended-wear contact lenses, eyelid disease, and disorders of the ocular surface are predominant contributing factors. Acute bacterial conjunctivitis occurs when sufficient bacteria are introduced into the fornices to overwhelm normal bacteriostatic and flushing mechanisms. Chronic conjunctivitis is associated with a constant adnexal source of bacteria and resolves when the source is successfully treated. Rapid diagnosis and treatment of bacterial keratitis are essential to limit stromal scarring and minimize visual loss.