Obstructive sleep apnoea is characterised by repetitive interruptions of breathing during sleep due to upper airway collapse. It affects sleep quality, daytime alertness and quality of life. It is associated with increased cardiovascular morbidity and mortality and an increased risk of road traffic accidents. Sleep apnoea is common among older people and its effects can be more severe than in younger people. The added impact is because of a physiological decline in sleep quality with age in most people and the increasing frequency of other comorbidities with increasing years that affect both sleep and daytime function. It is important to be alert to the diagnosis, bearing in mind these other influences on sleep quality. The diagnosis is generally straightforward once appropriate tests are performed. Treatment is aimed at minimising upper airway obstruction during sleep and the most effective therapy is continuous positive airway pressure. Weight loss can also be effective. Other management options, including surgery, mandibular advancement devices and drug treatment, are less effective, but there are interesting advances in the understanding of the pharmacology of the upper airway. Specific serotonergic agonists hold the greatest potential for a useful drug treatment for this widespread and debilitating condition.