This study examines the interconnections between domestic regulatory reform and market openness by drawing on OECD's earlier work on the regulatory aspects of trade. Part 1 considers how domestic regulations and regulatory reform affect market openness. It shows how with the help of advanced regulatory reform tools and approaches governments can create regulations and regulatory procedures that efficiently meet their policy objectives while at the same time supporting market access. Part 2 demonstrates that international market opening can contribute to facilitating domestic regulatory reform. Trade agreements signed on the multilateral, regional and bilateral levels can promote general principles or specific elements of good regulation and help guide or drive countries' individual regulatory reform efforts. Finally, part 3 analyzes the mutual benefits of regulatory reform and an open multilateral system for trade and investment. It is argued that by increasing domestic economic efficiency, raising the international competitiveness of domestic enterprises and reducing barriers to trade and investment, traderelated regulatory reform enables countries to take better advantage of trade liberalization and of open global markets.