Episcleritis and scleritis describe chronic inflammation of the outermost coats of the eye, and frequently occur as ocular complications of rheumatological disease. It is important to distinguish them, as episcleritis is usually a mild, self-limiting condition, but scleritis is frequently painful and has vision-threatening complications. Necrotising scleritis is a variant which is associated with the vasculitides, especially Wegener's granulomatosis, and is an ocular emergency that can damage the integrity of the globe if not treated urgently with high-dose immunosuppression. This article reviews the pathophysiology and clinical features of the different variants of episcleritis and scleritis, and also discusses current and emerging treatment modalities, including the biological agents and the putative role of periocular corticosteroid injections. © 2011 Bentham Science Publishers Ltd.