The purpose of the present study was to examine the construct validity and reliability of the Brief Symptom Inventory-18 (BSI-18) in 1,115 low-income Latina mothers. Exploratory factor analyses conducted in half of the sample supported a one-factor solution, which was subsequently confirmed in the remainder of the sample using confirmatory factor analyses. Contrary to its purported multidimensional structure, the BSI-18 measures a single dimension of general psychological distress in this sample of Latina mothers. Nevertheless, the results provide evidence that the symptoms composing the BSI-18 are meaningful expressions of general psychological distress among low-income Latina mothers. The validity of the BSI-18 as a measure of general distress was further supported by its correlations with theoretically relevant constructs. The BSI-18's reliability was evidenced in its demonstration of high internal consistency. The BSI-18 has utility for community psychologists and researchers as a general measure of psychological distress. For example, it could be given to low-income Latina samples in community-based interventions in which psychological distress might be a construct of interest. However, further research is needed to determine clinical cutoff scores for this population. © 2005 Wiley Periodicals, Inc. J Comm Psychol 33: 139–155, 2005.