The aim of this cross-sectional study was to analyze the typical aging process in adults with Down syndrome, focusing on its variability. The sample comprised 120 adults with Down syndrome who were free of dementia. Ages ranged from 20 to 69 years. Each participant was assessed on cognitive functioning and social adaptation, and was checked for the presence of psychopathological disorders. Results revealed an age-related deterioration in both cognitive and social adaptation skills, the extent of this decline depending on the dimension under scrutiny, and interindividual variability in aging profiles.