Sleep health is understood as a key factor in lifelong health and for social participation, function, and satisfaction. In later life, insomnia and other sleep disturbances are common. Insomnia is experienced as poor, disrupted, or insufficient sleep associated with significant daytime impairments including increased fatigue or reduced energy, impaired cognitive function, and increased mood disturbance. Poor sleep is associated with negative outcomes across a range of dimensions that impair quality of life, increases risk for other diseases, and may interact negatively with the progression and treatment of other disorders. Evidence for effective psychological interventions to improve sleep in later life, specifically cognitive behavioral therapy for insomnia, is robust and well described. Good sleep should be understood as a substrate for psychological health and a reasonable expectation in later life.