Acute acquired comitant esotropia is characterized by a dramatic onset of a relatively large angle of esotropia with diplopia and minimal refractive error. Two children, aged 41/2 and 61/2, who suddenly developed a nonaccommodative comitant esotropia are presented. There was no preceding trauma or febrile illness, and neurologic evaluation (including CT scans and Tensilon testing) was normal. Bimedial recession provided satisfactory alignment.