Sleep and circadian rhythm disturbances are prevalent in older populations. Numerous factors can affect sleep, including medications, living environment and physical, mental and psychosocial factors (e.g. loneliness and stress). Sleep architecture changes with aging, with less deep sleep (slow wave sleep) and an increased frequency of awakenings after sleep onset. Benzodiazepines, Z-drugs and low doses of the tricyclic antidepressant doxepin have modest positive benefits for sleep complaints, but side effects are a concern in older people because they include an increased risk of falls, fractures and cognitive impairment. Somnolence can be prolonged in older adults. Melatonin has very modest effects on sleep initiation in older adults, although appears safe. Overall, the effects of pharmacological treatments are modest and there are concerns about the efficacy and safety of their ongoing use. There is strong evidence for non-pharmacological interventions, including cognitive and behavioural strategies, to improve sleep. These have at least comparable efficacy to pharmacological interventions, fewer adverse effects and are more likely to have longer-term, sustained benefits. Sleep complaints in older adults need to be approached on a patient-by-patient basis, and medication should be reviewed frequently, with preference to limit pharmacological intervention as far as practicable.