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 International English Language Testing System, is an international standardized test of English language proficiency for non-native English language speakers. It is jointly managed by the British Council, IDP: IELTS Australia and Cambridge Assessment English, and was established in 1989. 

IELTS is accepted by most Australian, British, Canadian, European, Irish and New Zealand academic institutions, by over 3,000 academic institutions in the United States, and by various professional organisations across the world.

SELT is the only Secure English Language Test approved by UK Visas and Immigration (UKVI) for visa customers applying both outside and inside the UK. It also meets requirements for immigration to Australia, where Test of English as a Foreign Language (TOEFL) and Pearson Test of English Academic are also accepted, and New Zealand. In Canada, IELTS, TEF, or CELPIP are accepted by the immigration authority.