In 1996 the Australian Longitudinal Study on Women's Health recruited a nationally representative sample of more than 40 000 women in three age cohorts, born in 1973-78, 1946-51 and 1921-26. At least six waves of 3-yearly surveys have been completed. Although the focus remains on factors affecting the health and well-being of women and their access to and use of health services across urban, rural and remote areas of Australia, the study has now been considerably expanded by linkage to other health data sets. For most women who have ever participated in the study, linked records are now available for: government-subsidized non-hospital services (e.g. all general practitioner visits); pharmaceutical prescriptions filled; national death index, including codes for multiple causes of death; aged care assessments and services; cancer registries; and, for most states and territories, hospital admissions and perinatal data. Additionally, a large cohort of women born in 1989-95 have been recruited. The data are available to approved collaborators, with more than 780 researchers using the data so far. Full details of the study materials and data access procedures are available at [http://www.alswh.org.au/].