The assessment of hearing impaired children is fraught with a number of problems. These include lack of valid assessment measures, faulty theoretical assumptions, lack of knowledge regarding the functioning of cognitive processes of these children, and biases against these children. This article briefly considers these issues and describes a study conducted with hearing impaired children. To examine these issues, scores on the Universal Nonverbal Intelligence Test were compared with Wechsler Intelligence Scale for Children-III Performance IQs. Subjects were 32 hearing-impaired residents of a state school for the deaf. Analyses indicated 1) all UNIT IQs and WISC-III PIQs were attenuated, and 2) mean UNIT IQs and PIQs did not differ for the total sample or by gender but were significantly different for a sub sample of middle school students. The inter-correlations among UNIT IQs and WISC-III PIQs and subtests were high (median r = 0.723), indicating that the UNIT FSIQs and WISC-III IQs share considerable conceptual overlap. (Contains 3 tables.)