A pterygium is a benign, usually progressive fibrovascular overgrowth of the conjunctiva usually arising at the inner canthus of the eye which may cause local symptoms, particularly if large and impinging on the cornea. The treatment of choice for symptomatic pterygia is surgical excision, but early proliferation of fibroblasts and vascular buds leads to recurrence in a large proportion of cases. We review the published results of adjuvant postoperative beta irradiation using an ophthalmic applicator containing strontium-90 which is effective at reducing recurrence to an acceptable level. This treatment is well tolerated in the short term, and although a number of late sequelae are recognized, these are extremely uncommon in everyday clinical practice.