Questionnaires concerning the incidence of memory failures in everyday life were used in a postal survey of the aftereffects of severe head injury. Several years after a severe injury, 50 patients were compared to 33 patients a similar period after a very mild injury. A questionnaire completed on behalf of each patient by someone living in daily contact with him appeared to have some validity as a memory measure. The pattern of memory failures reported was similar to that found in a previous study and this may primarily reflect the ease with which certain forms of memory failure can be observed. A questionnaire completed by the patients themselves had little validity, possibly because severely injured patients could not recall their own memory failures. Only a minority of severely injured patients were reported to be significantly handicapped by memory failures at this stage in their recovery.