However, international tax is an important part of the work of many tax advisers. However, a key characteristic of international advisers is that they have a variety of backgrounds and typically spend time in more than one country. The Institute recognised a demand both in and outside the UK for a specialist Diploma to meet the needs of international tax practitioners in the Corporate area, and in 2003 introduced the Advanced Diploma in International Taxation. The overall standard of the Diploma is comparable to the CTA in the UK.

The Institute considers that there are significant benefits in having an internationally recognised Diploma. Just as having the CTA indicates that the individual has a certain level of competence in UK tax matters, so the Diploma indicates a high level of competence in International Taxation and a successful candidate needs to be able to demonstrate knowledge in three areas:

• The principles of international taxation;
• In-depth knowledge of international tax issues for their primary jurisdiction;
• An awareness of basic tax issues, particularly in relation to international tax, in at least one secondary jurisdiction.

It is possible to substitute a thesis for one examination paper.

A key longer-term goal is to make this a truly international qualification. If that can be achieved, then advisers moving from one country to another could have a common qualification as an important credential and the Institute is working towards achieving recognition of the Diploma by fellow Tax Institutes around the world. Consideration will be given in the future to establishing examination centres outside the UK.

The Diploma is supervised by an Academic Board of distinguished international tax practitioners.

Holders of the Diploma are entitled to use the designatory letters "ADIT" after their name.

The Diploma is a free-standing qualification which will not give the right to membership of The Chartered Institute of Taxation or confer any of the benefits of membership.

Diploma holders are also eligible to claim exemption from Paper II of the CIOT's Chartered Tax Adviser examination.