While most ocular infections are benign, others can be associated with devastating visual consequences. Most patients present with either ocular discharge, visual symptoms or a red or painful eye. The primary care physician is usually the first to evaluate these patients. We have separated ocular infections into 3 groups. Infections affecting the cornea and conjunctiva often present with eye pain and a red eye; noninfectious aetiologies can have a similar presentation. Infections inside the eye (endophthalmitis) often have devastating consequences. They usually occur following penetrating ocular trauma or after intraocular surgery. Prompt referral to an ophthalmologist is crucial. Infections in the soft tissue surrounding the eye (ocular adnexa and orbit) can involve the eye indirectly and can spread from the orbit into the brain. The purpose of this article is to review ocular infections and current opinion regarding treatment. A general guideline should be that the approach to treatment be governed by the severity of symptoms and the magnitude of possible consequences. Mild external infections can be typically treated empirically. Severe conjunctivitis, and any corneal infection, require aggressive management, often including cultures and broad spectrum antibiotics; cultures are often used to guide treatment. Devastating vision loss can occur, even with aggressive management. Preseptal cellulitis in adults and older children can be managed conservatively with oral antibiotics if the orbit and optic nerve are not involved and the patient is otherwise healthy. Orbital or optic nerve involvement, on the other hand, demands orbital imaging and more aggressive intervention. Patients who have had recent surgery are at risk for developing endophthalmitis. Complaints of pain or a red eye must be taken very seriously. These patients must be considered to have an intraocular infection until it can be ruled out, and should be aggressively managed by a physician trained in eye diseases and surgery.