Motowidlo, Borman, and Schmit (1997) proposed the theory of individual differences in task and contextual performance. The theory posits that task performance is predicted by cognitive ability though task habits, skills, and knowledge, whereas contextual performance is predicted by personality through contextual habits, skills, and knowledge. In this study, their theory was tested with the use of the Armed Forces Qualification Test (AFQT) as a measure of cognitive ability, the Navy Rating Protocol (NRP) as a measure of task and contextual performance, and the Navy Computer Adaptive Personality Scales (NCAPS) as a measure of personality. NRP scales were divided into contextual and task performance dimensions and personality traits were hypothesized to predict contextual performance, whereas cognitive ability was hypothesized to predict task performance. Results showed that the AFQT was significantly predictive of all contextual performance dimensions, and many of the personality dimensions did not provide incremental validity. Personality was only able to provide incremental validity beyond the AFQT for two contextual dimensions. Furthermore, the AFQT was only predictive of one of the task performance dimensions hypothesized. Because results appear to be mixed, more research will need to be conducted on Motowidlo et al.’s theory of task and contextual performance in order to provide support for the theory.