Council of Europe & OECD 
Convention on Mutual Administrative Assistance in Tax Matters Twentieth Anniversary Edition [PDF ebook] 

This Convention offers tax authorities a legal framework for co-operating across borders without violating the sovereignty of other countries or the rights of taxpayers. Includes the text of the convention and commentaries. The Convention entered into force in 1995, and interest is growing, with almost half of the countries that have signed the Convention doing so in the last five years. This reflects the growing importance of exchange of information and other forms of co-operation between tax administrations in an increasingly borderless business and financial world. This Twentieth Anniversary edition includes the text of the convention as well as commentaries.