Exchange of information: obligates inter state tax information sharing with confidentiality safeguards and limited exceptions. Exchange of information obliges Contracting States' competent authorities to exchange foreseeably relevant tax information for implementing the Convention or administering/enforcing covered domestic tax laws, subject to secrecy and use limitations. Information must be treated as secret and disclosed only to authorized assessment, collection, enforcement, prosecutorial, appeals or oversight authorities and used solely for those purposes, though public court disclosure and mutually authorised secondary uses are permitted. States need not adopt measures contrary to domestic law, supply unobtainable information, or disclose trade or public policy sensitive secrets, but may not refuse requests solely because information is held by financial intermediaries or because they lack a domestic interest.