The myeloproliferative disorder, essential thrombocythaemia (ET), is extremely rare in children. In adults, thrombosis is the most common complication whereas a low number of children develop thrombosis and/or haemorrhages. Diagnosis of ET is often difficult, but identifying ET from other causes of thrombocytosis is essential, otherwise therapy may be ineffective as the wrong disease will be treated. Only anecdotal experiences have been published with regard to the treatment of paediatric ET. A watch-and-wait strategy seems appropriate in asymptomatic cases and low-dose aspirin should be used to reduce microvascular disturbances. Anagrelide or IFNs may be considered as first-line, and hydroxyurea as second-line therapy. Anagrelide may become the treatment of choice for ET in children if a lack of leukaemogenic potential is confirmed.