The Chief Constable of Sussex Police will leave his post next year to become president of the Association of Chief Police Officers (Acpo).
Ken Jones has been Sussex Police's chief constable for four years
Ken Jones will take over from current president Chris Fox in April 2006 and will serve a three-year term.
Mr Jones, who has been chief constable with the Sussex force since 2001, is likely to become one of the most high-profile police figures in the UK.
He said he intended to "champion modernisation and much-needed change".
As Acpo president, Mr Jones will be an influential contributor to the debate on future reform of the police service.
The role of Acpo is to develop policy and guidance for the police service and to provide professional advice to government.
Its presidency is decided by a ballot of members.
Mr Jones said: "As president I intend to positively develop national policing policy in ways which actively build on the local policing style which we have created here.
Chris Fox said there was much to achieve in his final seven months
"I also intend to champion modernisation and much-needed change in ways which acknowledge our traditions, values and ethos."
Mr Jones took over as the leader of Sussex Police from Paul Whitehouse, who resigned after criticism following the fatal shooting by police of James Ashley in Hastings in 1998.
Mr Jones sent an internal message to staff of the force on Wednesday saying "in a few hectic years, we have managed to restore Sussex to its rightful place".
Mr Fox, the current Acpo president, said he was delighted with the choice of his successor and added: "This is a very important role in a time when the police service is driving forward huge changes.
"With the fast pace of change, there remains much to do over the next seven months before the new president takes up his position."
Peter Jones, chairman of Sussex Police Authority, said he had offered Mr Jones his heartiest congratulations but regretted that the county would be losing a "very fine chief constable".
No announcement has been made yet over who will replace Mr Jones as chief constable.