AbstractThe eye is probably the most common site for the development of allergic inflammatory disorders, because it has no mechanical barrier to prevent the impact of allergens such as pollen on its surface. Physicians in various specialties and subspecialties who provide some form of primary care frequently encounter various forms of inflammation of the anterior surface of the eye that present as “red eye.” However, the eye is rarely the only target for an immediate allergic‐type response. Typically, many patients have other combinations of allergic disorders, such as rhinoconjunctivitis, rhinosinusitis, asthma, urticaria, or eczema. Even so, ocular signs and symptoms can frequently be the most prominent features of the entire allergic response for which a patient visits his or her physician. An improved differential diagnosis provides the basis for improved treatment algorithms. Over the past 20 years, we have witnessed an astonishing growth in therapeutic advances, ranging essentially from derivatives of simple aspirin to various newly developed biologic immunomodulatory agents, utilizing implantable drug‐delivery devices that exceed the safety and efficacy of those available for other organ systems, and resorting to advanced surgical techniques for the correction of sight‐threatening, disease‐related complications. Overall, with the expanding knowledge base, the intricacy of ocular inflammation appears to be becoming ever more manageable and, with the team approach between the primary care physician, the ophthalmologist, and the clinical allergist/immunologist, the new “immuno‐ophthalmology” approach improves patient outcomes. Mt Sinai J Med 78:740–758, 2011. © 2011 Mount Sinai School of Medicine