This paper investigates the effectiveness of equity-based compensation in mitigating the effects of agency costs on the valuation of single-segment and multi-segment firms. In a sample of 4182 firm-year observations during the period 1993–1998, we find that firms with high equity-based compensation have higher valuation than firms with low equity-based compensation. This is true in both single-segment and multi-segment firms. The effect of equity-based compensation for multi-segment firms, where agency costs are expected to be higher, is much greater than for single-segment firms. Also, the negative value-effect of diversification is less for firms with high equity-based compensation.