General intelligence, Big Five personality traits, and the construct Work Drive were studied in relation to two measures of collegiate academic performance: a single course grade received by undergraduate students in an introductory psychology course, and self-reported GPA. General intelligence and Work Drive were found to be significantly positively related to both course grade and GPA, while one Big Five trait (Emotional Stability) was related to course grade only. Hierarchical multiple regression analysis revealed the incremental validity of Work Drive beyond Emotional Stability and over and above general intelligence: Work Drive accounted for 7% and 14% of unique course grade and GPA variance, respectively, when Emotional Stability was entered last; and Work Drive accounted for 6% and 13% of unique course grade and GPA variance, respectively, when Work Drive was entered last. In both cases, Emotional Stability did not provide significant unique variance. Findings are presented and discussed in the context of examining how cognitive and non-cognitive variables predict academic performance, and in terms of implications for using course grade versus GPA as a criterion for collegiate academic performance.