Despite the concentration of the compensation consulting industry, where a few large firms dominate the market and serve multiple clients, little attention has been given to the implications of shared consultants on compensation practices. This study investigates the impact of shared compensation consultants on peer firm overlap in relative performance evaluation (RPE) in executive compensation. We find that firms sharing the same consultant have significantly higher RPE peer overlap compared to those without a common consultant. This effect is robust to controlling for various firm-pair characteristics and remains significant after addressing potential endogeneity through exogenous shocks, such as consultant acquisition and spin-off. Cross-sectional tests suggest that industry knowledge and legitimacy needs are key channels driving this overlap. Additionally, we show that the high overlap indeed reflects the commonalities between the firm pairs, and find that shared consultants encourage managers to take more idiosyncratic risks, consistent with optimal contracting theory.