Red eye is a common ocular presentation in primary care, and there are several challenges that healthcare practitioners may encounter when caring for such patients. The main ocular conditions that can give rise to red eye are: primary acute angle closure glaucoma, acute iritis, dry eye, blepharitis and conjunctivitis. Red eye can be classified as sight-threatening or non-sight-threatening. Many patients presenting with painless red eye and normal vision usually recover well. However, when red eye is associated with pain, photophobia, watering and blurred vision, it is potentially sight-threatening and must be addressed urgently. Therefore, it is vital for healthcare practitioners to be able to undertake a careful assessment of the patient and make an accurate diagnosis early. This article provides an overview of the common causes of red eye encountered in general practice or an eye clinic. It discusses the nurse’s role in the care and management of patients with red eye, with reference to patient assessment, the skills required to make an accurate diagnosis, treatment and health promotion.