This literature review on young adults with mental retardation brings together two previously disparate areas of research, community integration and young adult development. After a discussion of various theories addressing the young adulthood stage of development, the paper summarizes research on young adults with mental retardation in the following domains: (1) social integration (findings emphasize the passive, solitary, family-dependent nature of their lives and the need to promote greater social integration); (2) recreational/leisure integration (stresses the need for greater opportunities to learn and enjoy recreational activities); (3) economic integration (points out that the right to manage one's own income should be respected as much as possible); and (4) support services (in the areas of residential, vocational, and other services) and barriers (especially attitudinal) to community integration. Includes 110 references. (DB)