A large body of evidence suggests that financial development is greater in countries that impose stricter regulatory requirements on their major stock exchanges, but this leaves open the question of whether or not such regulation should be uniformly applied to all equity trading platforms within a country. On the one hand, regulatory variation permits a wider choice of investment opportunities for investors, lowers the cost of capital for some firms, and enhances price discovery and efficiency. On the other hand, the presence of lightly regulated exchanges can potentially have adverse spillover implications for a country’s other financial markets.