The Reiss Screen for Maladaptive Behavior and a modified version of the MMPI-168 were administered to 65 residents of a state mental institution diagnosed with mild or moderate mental retardation. Possible associations between the two screening instruments were then examined. Significant correlations were obtained between four scales of the Reiss Screen and Scales F, K, 1, 6, and 7 of the MMPI-168. These results support the clinical efficacy of both instruments in screening for behavioral pathology in mentally retarded persons. However, some scales purported to assess similar psychological constructs failed to show expected positive associations.