This study investigated the role of career competencies as a mediator in the Job Demands - Resources model. Structural equation modeling with data from 305 young employed persons aged 16-30 years showed that career competencies are positively related to job resources and work engagement, but not to job demands and emotional exhaustion. Furthermore, career competencies had a partially mediating effect on the relationship between job resources and work engagement, and job resources had a partially mediating effect on the relationship between career competencies and work engagement. These findings suggest that career competencies may act in a similar way as personal resources in fostering work engagement. Our results underline the importance of combining research on job design and career development, and suggest that career competencies may have a role in stimulating employee wellbeing. Career counselors and HR programs may benefit from this insight by simultaneously increasing job resources and career competencies to increase employee wellbeing. © 2013 Elsevier Inc.