Scope and Method of Study: The purpose of this study was to explore the relationships between the expression of critical thinking and motivational orientation (i.e. autonomy, controlled and impersonal) and the relationship between expressed critical thinking and self-theories of intelligence mindsets (i.e. entity vs. incremental). Correlation and multiple regression analyses were performed to examine the relationship between motivation orientations and mindsets on critical thinking. The sample for this study consisted of 106 college students recruited from three Midwestern universities with ages from 18 to 25. Findings and Conclusions: Regression analysis revealed a significant relationship between autonomy and controlled motivation orientations and critical thinking. Autonomy orientations had a positive predictive relationship with critical thinking while controlled orientation had a negative predictive relationship with critical thinking. Neither the impersonal orientation nor mindsets indicated a significant relationship with the expression of critical thinking. This finding is consistent with the interpretation that the autonomy orientation may function similarly to the proposed 'critical thinking disposition' so prevalent in the critical thinking literature. Rather than an inherent psychological trait being responsible for the exhibition of critical thinking (i.e. disposition), the expression of critical thinking may rely rather heavily on motivational factors instead. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]