Background: Children with Down syndrome (DS) suffer from sleep problems, including sleep maintenance problems, as well as snoring, and other symptoms of disordered breathing. To examine sleep in DS, we gave parents a questionnaire assessing their child's sleep. Materials and methods: The parents of 35 children with DS (mean age = 12.65 years, range = 7-18 years) completed the 33-item Children's Sleep Habits Questionnaire. Results: Eighty-five per cent of our sample had sleep disturbance scores in the clinical range (mean = 48.63, SD = 7.15, range = 34-64). Our sample also had significantly elevated scores on the Bedtime Resistance, Sleep Anxiety, Night Wakings, Parasomnias, Sleep Disordered Breathing and Daytime Sleepiness subscales. Conclusions: Children with DS are at risk for developing symptoms of sleep disordered breathing, and may have additional sleep problems that are unrelated to sleep disordered breathing.