The winners of the Host City Bid Process will be announced at the end of September 2015.
The eighth and ninth annual summits will bring together 1,350 young leaders from more than 190 countries. The young delegates will be joined by global dignitaries who will mentor them in their decisions. In previous years these have included Bill Clinton, Kofi Annan, Mary Robinson, Professor Muhammad Yunus, Archbishop Desmond Tutu, Arianna Huffington and Sir Richard Branson.
One Young World co-founder Kate Robertson said: "As always, One Young World is honoured that such a variety of world cities want to host this unique event. We believe that hosting One Young World can have a meaningful impact on the young populations of the Host Cities and are delighted that we have four such iconic locations who want to welcome our delegates."
More than 1,400 delegates from 196 countries attended the One Young World Summit in Dublin in 2014, which showcased Ireland as a business destination.
The 2015 One Young World Summit will take place in Bangkok, Thailand, before the baton is handed to Ottowa, Canada for the 2017 summit.
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