This chapter makes a distinction between studies of sleepiness and studies of napping. In considering difficulties with excessive daytime sleepiness among older adults, one key factor is poor quality nighttime sleep. Many studies have found that depression is associated with excessive daytime sleepiness (EDS), with some of those studies focusing specifically on older adults. One key treatment consideration in the management of daytime sleepiness among older adults is to address primary sleep disorders that disrupt nighttime sleep. One such example is a randomized controlled trial of the effect of treatment of sleep apnea on daytime functioning in patients with Alzhiemer's disease (AD). Studies show that patients with dementia, particularly with AD, commonly suffer from daytime sleepiness. Studies also highlight that increased exposure to bright light, particularly when combined with efforts to reduce time in bed during the day, may be an effective method for decreasing daytime sleepiness.