As employees grow older, do their attitudes regarding work change over time? Can such long-term changes be understood from a personality development perspective? The present study addressed these fundamental questions by tracking 504 young professionals' work attitudes (i.e., job satisfaction and work involvement) and Big Five personality traits over the first 15years of their professional career. We specifically investigated whether trait changes drive peoples' changing attitudes, a mechanism we called maturation of work attitudes. Latent change models first indicated significant associations between traits and attitudes at the beginning of the career, and mean-level changes in Big Five traits (i.e., increases in Agreeableness and Conscientiousness and decreases in Neuroticism) in the direction of greater functional maturity. Although no significant mean-level changes in work attitudes were observed, results regarding correlated change indicated that variability in attitude change was related to variability in trait change and that this indeed signaled a maturational process. Finally, reciprocal effect estimates highlighted bidirectional relations between personality and attitudes over time. It is discussed how these results (i) provide a better understanding of potential age effects on work-related attitudes and (ii) imply a revision of the traditional dispositional approach to attitudes.