The speech sound discrimination abilities of 15 normal-hearing and 15 sensorineural hearing-impaired subjects between 55 and 65 years of age were assessed using videotaped presentations of the Nonsense Syllable Test (NST). Stimuli were presented in auditory (A), visual (V), and auditory-visual (AV) modes. All subjects received the stimuli in two trials for each presentation mode; hearing-impaired subjects were unaided for the first, and wore their own hearing aids for the second. Responses were transcribed phonemically and were scored by the phoneme method. Intra- and interjudge reliability was greater than 90%. Mean phoneme discrimination scores were plotted for each group across the three presentation modes. The results revealed that: both groups' performance improved from V to A to AV modes, but differences were apparent in the amount of increase across modes within each group; the NST differentiated between groups in the A and AV modes, but not in the V mode; the NST identified "poor" speechreaders in each group under both V and AV conditions; and consonant errors in the V mode formed seven homophenous categories based on place of articulation. The NST can be a useful screening test in auditory rehabilitation to distinguish those hearing-impaired persons who naturally take advantage of visual cues from those who do not.