About four million Americans currently live with Alzheimer's disease (AD) or related forms of dementia. Because the disease process impairs language, insight, and judgment, family members become "caregivers." These caregivers, either in part or in full, often make decisions on patients' behalf. This Issue Brief summarizes a series of studies that describe how caregivers make decisions for AD patients, and caregiver perspectives on the quality of life for relatives with AD.