Background: This study was carried out to determine why women caring for men report more burden than other caregivers, and to further examine the role of care-recipient problem behaviors as determinants of burden. Method: A sample of 557 primary caregivers of community-dwelling individuals referred to a memory clinic was used. All care-recipients had a diagnosis of Alzheimer's disease (NINCDS-ADRDA). Data on care-recipient function, caregiver attributes, external supports and caregiver burden were obtained on the first visit. Hierarchical regression models were used to determine the contribution of gender, after controlling for care-recipient status, caregiver attributes, and external supports. Results: This model explained 46% of the variability in caregiver "role burden", with care-recipient problem behaviors and dependence in instrumental activities of daily living. The caregiver/care-recipient gender interaction explained an additional 4% of the variance (p = 0.001); women caring for men scored 5.61 higher on the burden scale than other caregivers. Specific problem behaviors (e.g., anger) were more problematic for women caregivers than men. Conclusion: These results indicate that the experience of men and women caregivers may be different despite seemingly identical circumstances, and highlight the need for interventions geared to the specific needs of women caregivers.