This study examined the relationship between proactive personality and career decision-making self-efficacy. In Study 1, the authors validated the Proactive Personality Scale-Korean Short Form, using the Rasch model with 315 participants, and found that fit statistics, point-measure correlations, and item difficulty estimates satisfy the construct validity criterion. In Study 2, the authors administered the Proactive Personality Scale, Career Decision-Making Self-Efficacy Scale, and Career Search Self-Efficacy Scale to 296 freshman and sophomore college students. Hierarchical regression analyses showed that proactive personality scores explain additional variance in both career decision-making self-efficacy and career search self-efficacy scores. Implications for theory and practice are discussed.