This chapter clarifies and differentiates changes in cognitive functioning among the oldest old at the group and individual levels. Cross-sectionally, the oldest old demonstrate normative differences of being more physically and cognitively frail compared to younger groups. More variation and successful aging is observed at the individual level. Some oldest-old individuals can perform at the same levels as adults 20 to 40 years younger. Recent literature has recognized that the concept of cognitive vitality transcends the absence of dementia or dementing processes. We seek to clarify the concept of cognitive vitality because it has not been well defined in the literature either theoretically or operationally. This chapter addresses the following questions: 1) What is cognitive vitality and how does it contribute to the well-being of older adults? 2) What factors or resources contribute to cognitive vitality among the oldest old? and 3) What new directions can be identified for future research
