This prospective study was designed to identify important clinical features in patients with recurrent acute tonsillitis. A total of 195 consecutive children aged from 1 to 16 years were examined and a history of recurrent acute tonsillitis recorded. Patients with obstructive sleep apnoea or recent acute tonsillitis were excluded. Tonsil size was measured on the Brodsky scale [Brodsky L. (1989) Paediatr Clin N Am 36, 1551], tonsil symmetry, cervical lymphadenopathy, and hyperaemia of the anterior pillars was recorded. Patients with a history of recurrent tonsillitis had larger tonsils than those without tonsillitis (P < 0.001). Tonsil asymmetry and cervical lymphadenopathy were more common in patients with recurrent tonsillitis (P < 0.001). Anterior pillar hyperaemia was also more frequent in recurrent tonsillitis (P < 0.01). In addition to the frequency and severity of tonsillitis it is suggested that the size and symmetry of the tonsils, plus cervical lymphadenopathy and anterior pillar hyperaemia should be taken into account when deciding which patients would benefit from tonsillectomy.