In a study of the relation between foot pain and disability, a cross-sectional analysis was performed using baseline data (1992-1995) from the Women's Health and Aging Study, a population-based study of 1,002 disabled women aged 65 years and older living in Baltimore, Maryland. Chronic and severe foot pain, defined as pain lasting 1 month or longer in the previous year, plus pain in the previous month rated severe (7-10 on a scale of 0 to 10), was reported by 14% of the women. Severe foot pain was more common in women who were younger (aged 65-74 years), obese, or had hand or knee osteoarthritis. Walking speed and five repeated chair stands were slower in women with foot pain. After adjustment for age, body mass index, race, education, self-rated health, smoking status, comorbidities, and number of other pain sites, severe foot pain was independently associated with increased risk for walking difficulty (adjusted odds ratio = 1.69, 95% confidence interval 1.10-2.59) and disability in activities of daily living (adjusted odds ratio = 1.91, 95% confidence interval 1.21-3.01). These findings suggest that severe foot pain may play a key role in disability in older women. Further studies are warranted to confirm these results longitudinally and to determine whether interventions to alleviate foot pain could reduce or prevent disability in older women.