This cross-sectional self-report study examined (1) whether family functioning (Family Functioning in Adolescence Questionnaire, FFAQ) and self-image (Piers-Harris Children's Self-Concept Scale) have independent associations with smoking and alcohol use and (2) whether self-image mediates the relationship between family functioning, smoking, and alcohol use among 1,598 Hispanic males and females in grades 7 through 12 in Los Angeles County, California, in 2001. The findings supported the main effects and, to some degree, the mediational effects that were hypothesized. Limitations and implications for this study are discussed, and directions for future research are suggested. This study was funded by the California Tobacco Related Disease Research Program.