The proposed research will examine the role of temporal processing in audiovisual speech integration for older and younger adults. Sensory and cognitive changes with age may degrade temporal processing in older adults. If time varying aspects of speech are salient to multimodal integration, then older adults should be impaired relative to younger adults for the coordination of intersensory information. Experiments will test the importance of perceptual speed and the temporal congruity of the modalities for detection of audiovisual speech. This research has implications for multimodal perception, temporal processing of speech, sensory and cognitive changes with age and communication across lifespan.