The theory of the firm suggests that firms should maximize profit by investing in safety until marginal cost is equal to the marginal benefit. This paper addresses motor carrier safety from the perspective of the fi rm, developing the theoretical framework for fi rm safety decisions. Additionally, this paper tests the relationship between fi rm safety performance and safety practices, new safety technologies, and fi rm marketing strategies. By testing the impact of the safety performance marketing strategy on carrier accident rates, it can be shown that firm managers have control over the safety performance of their firms through management decisions.