Embolisation is one of the three treatments of a brain arteriovenous malformation (AVM), ruptured or unruptured, and is used on its own or combined with microsurgery or stereotactic radiosurgery (SRS). Planning starts with what the embolisation is for and whether the lesion could be cured by embolisation alone, which depends on its angioarchitecture. Liquid embolic agents are then injected into the nidus through a feeding artery or, in selected small lesions, retrogradely through the draining vein. Haemorrhage is the main complication of the procedure. Follow-up covers how cure is confirmed and how long the nidus is watched for recurrence.