Study Objectives: To measure sleeping difficulty and sleep quality among older women, explore experience and attitudes towards sleep, and test for negative association between difficulty sleeping and health-related quality of life. Design: Four-year longitudinal study. Setting: Women were participants in the Australian Longitudinal Study on Women's Health. Participants: Women were sampled according to use of sleeping medication and classified into 4 groups: sleeping badly and using sleeping medications; not sleeping badly, but using sleeping medications; sleeping badly, not using sleeping medications; not sleeping badly, not using sleeping medications. Interventions: None. Measurements and Results: Sleeping difficulty and sleeping-medication use were measured at Survey 1, Survey 2 (3 years later), and Survey 3 (4 years later). Survey 3 included: Nottingham Health Profile Sleep Subscale, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Geriatric Depression Scale, Duke Social Support Index, Medical Outcomes Study Short-Form 36-item Health Survey, and a 21-item life events scale. Survey 3 was returned by 1011 women (84%). Sleeping problems were negatively associated with SF-36 subscale scores. Most associations remained significant after comorbid conditions, Geriatric Depression Scale, life events scores, and medication use were added to models. Most women with sleeping problems (72%) sought help from a doctor, and 54% used prescribed sleeping medications in the past month. Conclusions: Sleeping difficulty is a serious symptom for older women and is associated with poorer quality of life. Some of this effect can be explained by comorbidities, depression scores, life events, and use of sleeping medications.