The purpose of this study was to determine whether the Memorial Symptom Assessment Scale (MSAS) could serve as a feasible, reliable, and valid tool for use in assessing the reports of 98 family caregivers (FC) on the symptom experiences of advanced stage cancer patients. The MSAS consists of subscales that describe psychological symptom distress (PSYCH), physical symptom distress (PHYS), and global symptom distress (Global Distress Index [MSAS-GDI]). The majority of FCs was able to respond to 32 MSAS symptom items; however, the greatest difficulty in FC responding occurred on the 'sexual interest' item. The mean PSYCH score was 1.42 (SD=0.83), the mean PHYS score was 0.96 (SD=0.67), and the mean MSAS-GDI was 1.46 (SD=0.24). Internal consistency was high in the PHYS (alpha=0.84), PSYCH (alpha=0.82), and MSAS-GDI (alpha=0.84) subscales. The average item-scale correlation ranged between r=0.50 and 0.60, indicating that the items were moderately to strongly correlated with the respective total subscales. The average inter-item correlation ranged between r=0.30 and 0.45, indicating that the items were moderately correlated with each other on the respective subscales. Good to excellent intraclass correlations (ICC) with patients' ordinal ratings support the concurrent validity and utility of the PHYS and MSAS-GDI subscales in FC populations who care for cancer patients in the home setting. Depending on the symptom, a range of slight to substantial Kappa values on dichotomous PHYS and PSYCH items, and fair ICC values on the ordinal PSYCH subscale provide questionable validity in FC populations caring for cancer patients.