This research addresses the question, can dispositional complements to situational self-congruity and situational functional congruity be identified? Self-image congruence research, which establishes a background for the situational impact of image and function-laden information, is reviewed. A theoretical rationale for developing dispositional measures is based on the interactionist paradigm in personality psychology combined with self-congruity theory and Blake and Mouton's orientation to tasks vs. people. It was hypothesized that the dispositional measures of self-congruity and functional congruity would moderate the relationship between situational self-congruity and functional congruity and the adoption of a brand of credit card. Results supporting this hypothesis would provide evidence of the nomological validity of the dispositional measures. A 2 x 2 x 2 x 2 factorial experimental design involving situational self-congruity, situational functional congruity, dispositional self-congruity and dispositional functional congruity was operationalized with ads for the Sierra Club credit card providing image and/or function-laden cues. Manipulation checks in the form of situational evaluations and behavioral measures in the form of credit card adoption were ascertained. Pretests were conducted to generate and refine items for the dispositional scale and to initially assess reliability and validity. Subsequently, a main study was conducted involving 320 students from two universities. The results show that the dispositional measures are highly reliable. Dispositional measures were also shown to have discriminant validity, however, the tests of nomological validity indicated that these measures may not be valid. This study emphasizes the importance of considering the coaction of situational and dispositional factors in understanding behavior. Limitations of the study, future research, and managerial implications of the findings are discussed. / Ph. D.