An optimal automotive seat backrest angle has not been identified, and currently, no universal method for analyzing sitting discomfort exists. The purposes of this study were to: (1) identify an optimum seat backrest angle or range of angles based on objective and subjective discomfort measures, and (2) evaluate existing methods for analyzing sitting discomfort data. Eight participants (4 male 4 female) completed three, two hour test sessions in a driving simulator. Results showed that subjective and objective measures were moderately correlated. The 120° seat backrest angle (measured from horizontal) resulted in less discomfort than the 105° and 135° seat backrest angles. Time weighted subjective discomfort ratings were the most effective subjective measure of sitting discomfort. Results also indicated that participants were able to identify discomfort differences for few body regions.