Moderate to severe sleep-disordered breathing (SDB) was identified in 20% (17 of 83) of children with spina bifida/myelomeningocele (SB/MM) at the Montreal Children's Hospital. The prevalence of SDB in patients with SB/MM elsewhere has not been determined. To establish current practices for identifying SDB in patients with SB/MM, questionnaires were sent to the coordinators of the 212 spina-bifida clinics in Canada and in the United States. Eighty-six (41%) questionnaires were returned, representing data on 13349 patients. Although 67% of the responding centers reported availability of cardiorespiratory sleep studies, only 996 (7.5%) patients with SB/MM had been tested and only 418 (3.1%) patients had been diagnosed with SDB. Across clinics, the prevalence of SDB was directly related to the frequency of testing. Of 380 deaths over the past 10 years, SDB and sudden unexplained death during sleep were identified as the cause of death in 49 (12.8%) and 34 (8.9%) patients, respectively. Moderate to severe SDB may not have been identified in a significant number of patients with SB/MM because they have not been tested.