ABSTRACT: Nearly 50% of older adults experience difficulty with sleeping, and 21% of older adults also experience cognitive complaints to which sleep difficulties can also contribute to poorer cognitive functioning. Combined, such sleep difficulties and age-related cognitive declines can contribute to poorer performance on everyday activities necessary for independence, quality of life, and successful aging. Activities that may be especially compromised are driving, instrumental activities of daily living, and employment. In nursing practice, it is necessary to understand the relationship between sleep and cognition and what contributes to poorer sleep hygiene and cognitive functioning, whether it is medications and polypharmacy, comorbidities, habits and lifestyle factors, or negative mood. Such an understanding can help nurses provide evidence-based interventions to improve sleep and cognition in older patients. In research, nurses must devise and test ways to improve sleep hygiene and cognitive functioning in older patients with methods such as sleep hygiene education and speed-of-processing training to ameliorate everyday functioning and quality of life.