This study explored the self-understanding of 77 young people with Down syndrome aged from 17 to 24 years, with verbal mental ages ranging from less than 2 years 6 months to 12 years 4 months. The aim was to determine whether the self-understanding of these young people followed a typical developmental pathway, whether they were making social comparisons to others, and if these comparisons were downward, upward or lateral. The data came from interviews with the young people and with their parents. Results confirmed the typical developmental progression in so far as relative comparisons to others were only made by those with significantly higher mental ages. These young people made more downward than upward comparisons, whereas parents largely referred to lateral comparisons. This again is similar to findings with people in general who tend to maintain their self-esteem by making downward comparisons. Aspirations were age appropriate, albeit with relatively low levels of cognitive understanding. Reference groups predominantly consisted of families and other young people with intellectual disabilities.