The drinks company has recruited Charlotte Lambkin, group communications director at BAE Systems, to take over from Wright.
She is set to join in January 2014 and Wright will depart on 31 March next year after a handover period.
Wright has been corporate relations director at Diageo since 2004, joining the company from Boots in 2000. Previously he worked in political comms roles for the SDP and the Liberal Democrats.
Former Bell Pottinger director Lambkin joined BAE in 2004. The aerospace firm is thought to have begun a search for Lambkin's replacement, considering both internal and external candidates.
Wright remained tight-lipped about his future plans, but scotched rumours he was planning to return to politics.
'I am pursuing a couple of discussions I don’t want to go in to but you can rule out speculation that I am going into politics to work for Nick Clegg. It will in a very general sense involve PR, and I’d expect my next role will involve doing very much as I am now.'
Wright worked closely with Diageo CEO Paul Walsh, who handed over the reins to Ivan Menezes earlier this year. Wright said both his and Walsh's exit had been planned for two years.
He added: 'As far as I’m concerned Charlotte is taking over leadership of the best team in corporate affairs she will start with a big advantage.'
One of the highest regarded in-house communicators, Lambkin commented: 'I joined BAE Systems for three years to gain some in-house experience and have been here ever since. This is down to the great people I work with and the important work done by the company. However, it’s time for a change and when I got the call from Diageo, I couldn’t turn them down.'
Ian King, CEO of BAE Systems, said: 'Charlotte has built a unified communications function which has increased the professionalism and transparency of our communications. I wish her every success in her new role.'
Paul Walsh said of Wright: ‘Ian has been a principal architect of Diageo’s reputation. It was he and his team who first articulated our ambition to be one of "the world’s most trusted and respected companies" and he has been a major contributor in our efforts to achieve it.’