Overqualification occurs when a person has a surplus of knowledge, experience, and qualifications relative to the job he or she holds. Approximately 15 to 20% of employees in industrialized countries are overqualified. Thus, overqualification has become an integral part of organizational reality. The present paper deals with overqualification in the context of career development. We first summarize attitudinal, well-being, and behavioral outcomes of overqualification. Afterwards, we will provide an overview of the relationships between overqualification and career-related outcomes. Based on the partly contrary findings, we develop a conceptual model. In particular, we postulate that overqualified individuals’ proactive behavior might be a signal for organizational decision makers, which in turn triggers career-enhancing changes and developments. Finally, we discuss practical implications of the empirical findings and the proposed model.