This paper assesses national and international responses to tax challenges presented by cross-border electronic commerce. Ten years after these challenges were first identified, a survey of national government reactions shows that many countries have not passed any significant tax legislation or administrative guidance with respect to the taxation of global e-commerce. This lack of action at the national level can be explained in large part by the leadership role taken by the Organization for Economic Cooperation and Development (OECD) in developing the guiding principles and, subsequently, the tax rules to confront the e-commerce tax challenges. The OECD’s general success with e-commerce tax reform demonstrates the OECD’s ability to act as a kind of informal (lower case) world tax organization, which emphasizes deliberation, consensus-building and the use of non-binding mechanisms such as the OECD model tax treaty. Moreover, the OECD’s success suggests that calls for a more formal (upper-case) World Tax Organization, which could impose binding tax rules on participating nations, may be misplaced.