The annual incidence of perianal abscess is estimated between 14 000 and 20 000 people in the UK, resulting in about 12 500 operations in the NHS each year. 1 A recent Swedish cohort study estimated the incidence at 16.1 per 100 000. 2 The true incidence may be higher, since many patients are treated with antibiotics in the community and some abscesses spontaneously regress or discharge. 2 3Patients usually present with an erythematous swelling near the anus and may be embarrassed or reluctant to seek treatment.They may present to a non-specialist in the first instance.This article provides information on the causes and different types of perianal abscess and an update on how they are best managed. PRACTICE