ABSTRACT The accommodative convergence/accommodation (AC/A) ratio is thought to be fixed throughout life. We present 11 patients who, in adulthood, show a situational increase in their AC/A ratio. Since all patients had a history of accommodative esotropia with and without a nonaccommodative component, we feel the situational increase in the AC/A ratio is in response to the additional effort needed to correct the patients' facultative hyperopia. These patients demonstrate the importance that all adults with acute onset of commitant esotropia and a history of accommodative esotropia should wear full correction before a prism is incorporated into their glasses or surgical intervention is considered.