This study explored the differences in student success outcomes between students enrolled in non-STEM and STEM corequisite mathematics courses at 18 postsecondary institutions across five academic years in West Virginia, using de-identified student data. The researcher analyzed this extant data to determine if student characteristics were predictors of success, as defined as passing the mathematics corequisite course, retention to the next semester, and earning a GPA of 2.0 or higher. The researcher also conducted analyses to understand if the differences in those outcomes between STEM and non-STEM courses were significant. This study identified statistically significant gaps in success for students who enrolled in STEM and non-STEM courses in retention and earning a GPA of 2.0 or higher. It further identified multiple student characteristics significantly predictive of passing a corequisite mathematics course (i.e., sex, race, Pell status, and mathematics course type), being retained to the next semester (i.e., sex, age, Pell status, and mathematics course type), and earning a GPA of 2.0 or higher (i.e., sex, age, race, Pell status, and mathematics course type), for students enrolled in both non-STEM and STEM mathematics corequisite courses at these institutions. [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.]