Student success is often treated as an observed variable, or something that you can measure directly with a single instrument. Single course outcomes such as final course grade or learning gain on an assessment have become synonymous with success in undergraduate science education research. Continually relying on these narrow course outcomes to define and measure success creates validity and reliability issues, as these outcomes are inconsistently measured and do not accurately represent success as a broad construct. To address these issues, I propose conceptualizing student success as a latent construct. This latent construct of success is measured indirectly by several course outcomes. Thus, course outcomes function as proxies, or indicators of success, instead of individual measures of success. In this study, several course outcomes, both cognitive and non-cognitive (affective) are conceptualized to be pieces of a single student success construct. These outcomes have previously been shown to be important indicators of student success in undergraduate introductory biology courses. This conceptualization was confirmed with Structural Equation Modeling and factor analysis. The effect of demographic, pre-college, and intervention variables on this latent construct of success was also analyzed. Finally, a partial credit Rasch model was used to place the course outcomes that make up the success construct on the same scale, and to create a new measure of success and assess the relative difficulty of each outcome. The results indicate that student success may be conceptualized and measured as a single, latent construct and that affective course outcomes contribute to the construct of success significantly. In addition, commonly used course outcomes, like final grade, are relatively easy for students to obtain and do not contribute to the success construct as much as some affective course outcomes. These results offer a creative and novel solution for how student success is both conceptualized and reliably measured in a potentially more valid way. [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://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]