The purpose of this study was to evaluate the role of social-cognitive variables in restrained eating, smoking, and weight control smoking. Overall, the results indicated Significant main effects of dietary restraint and smoking on dieting- and smoking-related social-cognitive variables. In addition, there were significant group differences for several social-cognitive variables related to weight control smoking. Overall, the results indicated significant main effects of dietary restraint and smoking on (a) several social-cognitive variables related to dieting and (b) several social-cognitive variables related to smoking. Interaction effects (i.e., restraint*smoking) were nonsignificant. In addition, weight control smokers differed from nonsmokers and non-weight control smokers on some (but not all) social-cognitive variables. For the most part, there were few significant differences in family variables (i.e., past and present family presence, family approval, and family pressures scores). However, there were numerous Significant differences in peer variables (i.e., past and present peer presence, pressures, and approval scores). These results indicate that peer modeling, pressures, and/or approval should be further explored for their potential impact on dieting, smoking, and weight control smoking behaviors in young people. There also were significant differences for expectancies (i.e., outcome expectancies, outcome values, and self-efficacy). Because of methodological concerns, this study was unable to fully assess the role of outcome expectancies on restrained eating, smoking, and weight control smoking behaviors. However, analyses that could be conducted on outcome expectancies provided significant results, and there were significant findings related to outcome values about dieting and weight control smoking. In addition, there also were Significant findings for self-efficacy related to eating, smoking, and weight control smoking. It is recommended that future research continue to investigate the role of outcome values and expectancies and self-efficacy in restrained eating, smoking, and weight control smoking. Exploratory analyses provided more support for the importance of expectancies in restrained eating, smoking, and weight control smoking behaviors. Also, specific behaviors were significant in predicting restrained eating and weight control smoking (i.e., dietary restraint was predicted by current dieting behavior, and weight control smoking was predicted by dietary restraint and number of previous quit attempts). These results once again suggest that intervention programs for any of the three behaviors should attempt to improve self-efficacy skills. In addition, programs aimed at restrained eaters and weight control smokers should attempt to challenge overly positive outcome values and expectancies related to smoking cessation and/or weight control and decrease negative weight-related behaviors. / Ph. D.