Sleep disorders are very common in childhood and are often amenable to simple advice and parental education. Questions about sleep should be an integral part of every paediatric consultation. Children with underlying syndromes or complex medical conditions often have multiple sleep issues. Excessive sleepiness in children requires careful history-taking and consideration of specialised investigation. Obstructive sleep apnoea (OSA) is a common condition in childhood with important health implications. The high prevalence of OSA warrants rigorous attempts to identify children at higher risk and manage them appropriately. Adenotonsillectomy is a highly efficacious therapy for paediatric OSA. A current major issue is to improve ways of distinguishing mild from severe OSA before a child undergoes adenotonsillectomy, as those with more severe disease are at increased risk of postoperative complications and should undergo adenotonsillectomy in a tertiary centre. Children with obesity and other comorbid conditions are at increased risk of persisting OSA despite adenotonsillectomy. Topical (nasal) steroids and/or anti-inflammatory agents have a role in the non-surgical treatment of mild OSA. Continuous positive airway pressure and orthodontic interventions are treatment options for treatment of persisting OSA in children.