Branchial cysts, sinuses and fistulae are reviewed with special reference to their origin, clinical features, pathology and treatment. The material consists of a survey of over 700 recorded cases, a series of 90 cases studied in retrospect with special reference to the pathology, and a personal experience of 42. It is suggested that a proportion of 'branchial cysts' do not arise from the branchial apparatus, but possibly may do so from epithelial inclusions in lymph nodes. It is accepted that branchial sinuses develop from the branchial apparatus, but there is little proof that such an entity as 'branchial fistula' exists.