This encyclopedia brings together a comprehensive collection of work highlighting established research and emerging science in all relevant disciplines in gerontology and population aging. It covers the breadth of the field, gives readers access to all major sub-fields, and illustrates their interconnectedness with other disciplines. With more than 1300 cross-disciplinary contributors-including anthropologists, biologists, economists, psychiatrists, public policy experts, sociologists, and others-the encyclopedia delves deep into key areas of gerontology and population aging such as ageism, biodemography, disablement, longevity, long-term care, and much more. Paying careful attention to empirical research and literature from around the globe, the encyclopedia is of interest to a wide audience that includes researchers, teachers and students, policy makers, (non)governmental agencies, public health practitioners, business planners, and many other individuals and organizations.