John was diagnosed with mild intellectual disability (ID) in kindergarten when he was having trouble learning letters and numbers and was engaging in disruptive behaviors. He had a psycho-educational assessment that demonstrated a full scale IQ score of 58 and an Adaptive Behavior Composite standard score of 63 on the Vineland Adaptive Behavior Scales. He was initially educated in a regular classroom with special education support, but as he fell further behind his classmates' academic skills, he spent increasing time in special education classrooms while going to mainstream classrooms for art and music. His parents attempted to arrange activities with typically developing peers but have found this to be increasingly difficult as he has gotten older. He is now 16 and entering his second year of high school. His parents have multiple concerns. Do they need to plan for John to live with them? Will John be able to be employed? John says he does not like school and he wants to work, but is this a good idea? If it is a good idea, how does one help him get a job? What is John's adult life going to be like?John's parents' questions are often placed to professionals involved in the care of a child or youth with an ID. No professional will be able to precisely predict John's adult activities as these activities will be influenced by a complex interaction between his strengths, weaknesses, interests, and experiences and the opportunities provided by his family, community, and society. Yet as a professional advising John and his family, having an accurate view of the range of possible outcomes for John is critical. An overly pessimistic view may discourage a family from seeking opportunities and services that could dramatically increase John's autonomy as an adult. On the other hand, an overly optimistic view might also interfere with appropriate planning and lead to frustration for John and his family.As we present a picture of the range of possible outcomes for John and others with ID, it is important to recognize that over the past 50 years, there has been a dramatic transformation in the opportunities and supports available to individuals with ID in the United States and many industrialized societies. Changes in the name and definition of ID as well as in public policy and legislation have altered where individuals with cognitive limitations live, how they are educated, and their opportunities for employment. After discussing the definition of ID, we will briefly review these changes in order to place what we know about the outcomes for individuals with ID in the context of this shifting environment. Further complicating the picture must be the recognition that there is great variability in the implementation of these policies and innovations. For many adults with ID, the promise of these changes to improve the functional status and quality of life is greater than the current reality. Thus, in discussing these outcomes, we will highlight disparities between what is currently achieved and the evidence for outcomes that a...