This study investigated the predictability of rational decision- making style on career decision-making status and treatment gains based on a computer-based career intervention. Decision-making style, in relation to pretreatment career status as well as its efficacy in predicting intervention outcomes, was also examined. Seventy-four undecided university students participated in the study. Results show that employing decision-making strategies based on an individual's preference significantly increased students' career decidedness and decreased career indecision, choice anxiety, and reason complexity. Rational decision-making style is positively associated with career decidedness and negatively associated with the exploration stage of decision making; it is not, however, predictive of treatment gains.