This chapter presents the causes of the aging process and the functional changes of Senescence. It assesses the progression of dementia along with the various stages of Alzheimer’s disease (AD). The chapter defines AD and related dementias based on fundamental criteria. It talks about recent studies, interventions, and treatments for AD. The chapter describes the financial and legal issues of caring for a patient/family member with AD. It then discusses legislation, social awareness efforts, health care proposals, and organizations that support AD patients and their family members. AD and vascular dementia are the most common neurological impairments associated with dementia. The mental status examination (MSE) is a general screening test for cognitive impairment and identifies psychiatric symptoms. Although there are no drugs proven to cure AD, the U.S. Food and Drug Administration (FDA) has approved the use of four drug treatments: Aricept^®, Exelon^®, Razadyne^®, and Namenda^®.