A study examined basic reading skills among men in prison, comparing poor and adequate readers with respect to comprehension, decoding, short-term memory, and speech perception. Subjects, 88 inmates of normal intelligence, normal hearing, and no significant speech abnormalities, at a minimum-security prison, were given reading comprehension tests and tests of listening perception. Subjects were divided into poor readers (less than sixth grade reading level) and adequate readers (greater than sixth grade level). Results indicated that poor readers were surprisingly uniform; they differed from good ones on several cognitive and linguistic measures. Results also indicated that among poor readers, the best predictors of comprehension are decoding and short-term memory and that poor readers have a hidden deficit in that they are more affected by noise when trying to perceive familiar spoken words. Findings suggest that adult poor readers strongly resemble poor readers in elementary school in the areas of short-term memory and decoding skills. (Seven tables and 7 figures of data are included; 34 references are attached.) (RS)