We show that, in competition between a developed country and a developing country over environmental standards and taxes, the developing country may have a “second‐mover advantage.” In our model, firms do not unanimously prefer lower environmental standard levels. We introduce this feature to an otherwise familiar model of fiscal competition. Four distinct outcomes can be characterized by varying the marginal cost to firms of an environmental externality: (1) the outcome may be efficient; (2) the developing country may be a “pollution haven”—a place to escape excessively high environmental standards in the developed country; (3) the developing country may “undercut” the developed country and attract all firms; (4) the developed country may be a pollution haven.