A number of different instruments have been devised for investigating individual differences in memory on the basis of subjective reports. One such questionnaire was mailed to individuals on a register of patients with multiple sclerosis, a condition that is known to be associated with objective impairments in cognition and memory. A similar questionnaire was enclosed to be completed about each patient by a close relative. The patients' and relatives' responses were found to share a factor structure identifying memory problems in five areas: receptive communication, route finding, absent-mindedness, face recognition, and expressive communication. These were dominated by a single second-order factor representing a global subjective memory impairment. There were some minor differences between the patients and relatives in their factor scores, but there was generally a high degree of concordance in their responses.