This paper examines the implications of environmental corporate social responsibility (CSR) for the environment-growth tradeoff and social optimum in a dynamic general equilibrium growth model. We show that environmental CSR activity loosens the tradeoff between the environment and growth, but it cannot achieve the social optimum. Firm participation in environmental CSR induces the perceived CSR of green consumers and increases their willingness to pay. Because the environmental CSR promotes more consumption and increases growth, the environment-growth tradeoff loosens up in the competitive equilibrium. However, to translate the CSR perceived benefits into their profits, firms need some degree of monopoly power to set their prices to capture the stronger demand. CSR is thus promoted as a marketing strategy to help companies achieve their competitive advantage, and becomes a way of product differentiation in the environment of monopolistic competition. Since monopoly power serves as a catalyst, CSR alone cannot achieve the first-best optimum in terms of the environment and growth by fully removing the distortions caused by market imperfection.
