This document discusses epiretinal membrane (ERM), a fibrocellular membrane that forms on the inner surface of the retina. It causes varying degrees of macular dysfunction. ERM can be idiopathic or secondary to conditions like retinal detachment repair. Symptoms include vision loss and metamorphopsia. Diagnosis is usually clinical but OCT and FFA can help. Treatment is usually vitrectomy to peel the membrane if it is causing visual symptoms. Outcomes are generally good with most patients improving, but recurrence or worse vision is possible.