OBJECTIVE: To examine the prevalence of articular hypermobility and its relationship to musculoskeletal pain in Icelandic 12-yr-olds, and to obtain baseline data for a prospective study on the subject. METHODS: A total of 267 12-yr-olds were examined for articular hypermobility by the Beighton criteria. The children also answered a questionnaire concerning musculoskeletal pain and injuries, sports and musical activity. RESULTS: The prevalence of hypermobility (defined as >/=4 Beighton criteria) was 40.5% in girls and 12.9% in boys. Despite slight trends for hypermobile subjects to be less active in sports and to report more joint pain, no correlation could be found between hypermobility and musculoskeletal symptoms. CONCLUSIONS: An unusually marked sex difference in hypermobility exists among Icelandic 12-yr-olds, but hypermobility does not seem to affect joint symptoms or leisure activities at this age.