More than 400 guests and 75 speakers are expected to attend the third annual event, described as "the new Davos".
The summit, from 17-19 March, will see senior government, corporate and financial figures gather at the Intercontinental London Park Lane Hotel.
The programme also includes dinners at the Saatchi Gallery and Science Museum, as well as field trips to locations including the Thanet offshore wind farm and the Olympic Park.
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It is the latest in a series of wins for Powwow, which has recently picked up business in the financial and FMCG sectors. Last month, it won a place on Nationwide Group's preferred supplier roster following a competitive tender. Its first work with Nationwide will be to assist with the management of the financial firm's AGM in July.