Many scholars have emphasized the importance of subjective performance evaluations in employment relationships to provide employees with appropriate effort incentives. While the previous literature has focused on subjective evaluations conducted directly by the firm owner (principal), we investigate when delegating subjective appraisals to managers (su-pervisors) is optimal. Managers are equipped with the expertise to better evaluate employ-ees ’ contributions to firm value, but can be biased in their evaluation because of potential collusion. We find that delegating performance appraisals to managers is optimal when employees ’ potential contributions to firm value are relatively low. However, to ensure the impartiality of managers, their ...