A program for use on a microcomputer was developed to assist in the diagnosis of strabismus. The matrix consists of 41 separate disorders and 59 facts (history and examination findings). The facts are answered in a yes/no format. The relationship between the fact and the disorder is weighted as to whether the fact is always present, usually present, sometimes present, not related, unlikely to be present, not usually present, or never present. The computer makes the diagnosis (or diagnoses) indicating the most likely disorder when several are possible from the information given. Over 300 patient files were tested with the program. Of the last 50 records reviewed (70 disorders), the computer diagnosis agreed with the clinical diagnosis in 91% of the cases. Continued refinement of the program should be able to improve this accuracy.