BACKGROUND: The prevalence of sleep problems in adulthood increases with age. While not all sleep changes are pathological in later life, severe disturbances may lead to depression, cognitive impairments, deterioration of quality of life, significant stresses for carers and increased healthcare costs. The most common treatment for sleep disorders (particularly insomnia) is pharmacological. The efficacy of non-drug interventions has been suggested to be slower than pharmacological methods, but with no risk of drug-related tolerance or dependency. Bright light treatment involves participants sitting in front of a "light box" which emits very high (typically 10,000 lux) fluorescent light for periods of around two hours daily. The timing of this light treatment will depend on the irregular timing of the participant's sleep pattern. OBJECTIVES: To assess the efficacy of bright light therapy in improving sleep quality (sleep timing in particular) amongst adults aged 60 and above. SEARCH STRATEGY: The following databases were searched: MEDLINE (1966 - January 2001); EMBASE (1980 - January 2001), CINAHL ( 1982 - January 2001; PsychINFO 1970 to 2001; The Cochrane Library (Issue 1, 2001); National Research Register (NRR ). Bibliographies of existing reviews in the area, as well as of all trial reports obtained, were searched. Experts in the field were consulted. SELECTION CRITERIA: Randomised controlled trials of bright light therapy for primary sleep problems where 80% or more of participants were over 60. Participants must have been screened to exclude those with dementia and/or depression. DATA COLLECTION AND ANALYSIS: Abstracts of studies identified in searches of electronic databases were read and assessed to determine whether they might meet the inclusion criteria. MAIN RESULTS: Reviewers found no trials on which to base conclusions for the effectiveness of this treatment. REVIEWER'S CONCLUSIONS: When the possible side-effects of standard treatment (hypnotics) are considered, there is a reasonable argument to be made for clinical use of non-pharmacological treatments. In view of the promising results of bright light therapy in other populations with problems of sleep timing, further research into their effectiveness with older adults would seem justifiable.