Mr. Callan created the Callan English-teaching system - in which people learn to speak and communicate in English very rapidly - in Italy during the 1960s. He marketed it as “English in a quarter of the time”, but the idea was pooh-poohed by others in the language teaching community.
Despite this, it went on to become a huge success and today the Callan Method is taught in 425 schools in 35 countries, with more than a million former pupils, including Nobel Prize winning writer Gabriel García Márquez.
Callan School London in Oxford Street is said to be the biggest single English language school in the world attracting about 2,000 pupils every day.
Callan passed away in early 2014. In addition to the Callan School, he was also noted for saving The Orchard Tea Gardens at Grantchester, a much-loved haunt for famous folk for more than a century.