The Commonwealth Institute (TCI) is a private English language test preparation and teaching institution with particular expertise in the INTERNATIONAL ENGLISH LANGUAGE TESTING SYSTEM (IELTS), the most widely recognized English language proficiency testing system in the world.

As a language center steeped in the IELTS, the Institute provides short courses designed to refresh and improve the English language skills of Filipino professionals to the level required by local as well as foreign employers in the U.S.A., Canada, the U.K., Ireland, Australia or New Zealand.