In this chapter, three sensory systems (hearing, vision, and balance/gait) are examined. We begin with a descriptive overview of individual differences and age difference patterns in sensory functioning. The pattern of how individual differences in sensory acuity might be related to performance in other psychological and behavioral domains is examined. We reveal a strong, negative pattern of age differences in all three senses studied. These negative age trends have implications for the classification of sensory impairment rates: Although participants in their 70s have levels of sensory acuity that might be classified, on average, as slightly or mildly impaired, by their 90s most participants evince levels that might be classified as moderately to severely impaired, not only in one but in multiple modalities. We also report prevalence rates for the use of commonly occurring compensatory devices and procedures (e.g., hearing aids, glasses, cataract operations). We report the following findings with regard to the relationship of sensory functioning to other domains of psychological and behavioral performance (e.g., intellectual functioning, basic and expanded everyday competence, personality characteristics, well-being, social network size):