This chapter discusses the cognitive and psychological disorders experienced by elders, including dementia, delirium, and depression. Depression is not a normal part of aging. Depression is treatable. Despite efforts to increase public awareness, evidence shows up to 66% of older adults are not receiving the care they need. The depressed client has an increased risk of suicidal ideation. Depressed people have 30 times the suicide risk compared to the general population. Suicide among older adults is particularly common. Although normal changes of aging result in a decrease in brain weight and a shift in the proportion of gray matter to white matter, the development of cognitive impairment (CI) (previously known as “dementia”) is not a normal change of aging. Delirium is defined as a transient state of global CI. Delirium may develop in both cognitively intact and cognitively impaired older adults. Prevention of delirium by risk factor minimization is essential.