The test reliability of two tests of family functioning--the Family Environment Scale (FES) and the Family Adaptability and Cohesion Evaluation Scales (FACES-II)--was studied in 111 Anglo American, Black American, and Mexican American Families. The sample included children in grades three to six, as well as adults. The FES was administered to the adults twice, with a one-week interval. FACES-II was administered to the children twice, separated by a week. Item analyses, internal consistency and test-retest reliability coefficients, and factor analyses were conducted. Results indicated that the cohesion, conflict, and active-recreation scales of the FES had more acceptable psychometric characteristics than the FACES-II. The test-retest reliability results were higher than the internal consistency coefficients, indicating that the measures detected reliable variance, but these were not sensitively reflected in the preidentified scales. Both internal consistency and test-retest reliability coefficients varied by ethnic group, with the highest reliability among Anglo respondents. It was concluded that investigators interested in the cohesion, conflict, or active-recreational dimensions of family functioning in minority group populations should use Moos' and Moos' Family Environment Scales. (GDC)