This book presents the relationship between intellectual functioning and sports performance for athletes with intellectual disabilities, as well as a discussion on the Computerised Cognitive test battery for Individuals with Intellectual Disabilities (CCIID), which was developed for that purpose. A literature review indicated that there is a significant difference between physical performance of athletes with and without intellectual disabilities, but so far, no studies have examined the association between the degree of intellectual functioning and sports performance for athletes with intellectual disabilities. This book investigates this relationship for different sports disciplines and examines the role of adaptive behaviour and different cognitive abilities using a wider range of cognitive information processing tests.