SSS is a visual perceptual dysfunction associated with an excessive sensitivity of the retina of the eye to particular frequencies of the light spectrum. Several studies indicate that SSS is a factor in reading disabilities. Individuals with this dysfunction report print and background distortions when attempting reading or writing tasks that may include blurring or movement of print, restricted span of recognition, and problems with sustaining focus. Such difficulties continue even after full optometric or opthamological examinations and prescribed corrective lenses. Six prisons, representing the spectrum of security levels and educational program delivery, participated in the current study. A sample of 155 inmates was selected from these sites based on age, gender, ethnicity, and attained education level. All subjects completed SSS prescreening; 72 subjects completed full screening. Of the 72 subjects, 11.1 percent had low levels of SSS; 18.1 percent had moderate levels; and 79.8 percent had high levels. When given remedial colored overlays, 55.6 percent of the subjects had considerable reading improvement; 33.3 percent improved moderately. This high incidence of inmate SSS is particularly significant when contrasted with the 12-14 percent of the non-incarcerated population estimated to have SSS. 2 tables and 22 references