The life expectancy for people with intellectual disability has risen dramatically in the past century and, in some locations, is approaching parity with the mainstream population. This outcome is resulting in individuals with an intellectual disability living into chronological old age in large numbers for the first time in world history. This new phenomenon is leading to uncertainty for families, friends, government, and service providers with respect to understanding what assistance is required to most appropriately support emerging population-wide aging-related issues. The purpose of this entry is to provide a general overview of supporting the healthy aging for people with intellectual disability. It is not possible to successfully cover all aspects of ageing in any single book chapter, and therefore, the focus of this chapter is on summarizing and outlining key concepts. Comparisons of how aging and intellectual disability have been conceptualized, both individually and in combination, are provided to explain modern perspectives and theoretical frameworks. A specific focus is placed on seminal research from the past four decades in the fields of both intellectual disability and aging to illustrate the evolution and development of the current understanding of healthy aging for people with intellectual disabilities.