Founder's Day is a three-four day event in the autumn term, usually October, that marks the school's founding and draws many ex-pupils from all parts of the world. The chief guest is usually a prominent person, and the events include exhibitions, productions of plays, yoga sessions, live bands, a fete and an orchestral concert given by members of the school's Music Society. Doon celebrated its 75th Founder's Day in 2010 and programmed events on an unprecedented scale. The event was christened "DS-75". Among the chief guests were the then President of India Pratibha Patil, King Jigme Khesar Namgyel Wangchuck of Bhutan, and Kapil Sibal, then minister of Human Resource Development). Pratibha Patil, in her address, urged the school authorities to make Doon a co-educational institution. One of the main events was a discussion, dubbed the "Chandbagh Debate", held between alumni including Vikram Seth, Kamal Nath, Manpreet Singh Badal, Jyotiraditya Madhavrao Scindia and retired headmaster Kanti Bajpai, on the topic "Can India lead?". It was moderated by television commentator Karan Thapar, an alumnus of the school.