Acute acquired comitant esotropia has been used to describe a dramatic onset of a relatively large angle of esotropia with diplopia and minimal refractive error. We describe six children aged 5 to 11 years who developed an acute non-accommodative esotropia with diplopia. Neurological examination, including CT scan, in each of these children gave negative results. We suggest that this is an unusual presentation of esotropia of undetermined aetiology. The diagnosis, clinical characteristics, and management are discussed.