The new head of the Civil Service will focus on cost cutting and "transformational change" and will be paid up to £200,000, it has been announced.
According to a job description for the new role released by the Cabinet Office, the new CEO is likely to come from the private sector and have a proven track record of managing a large complex company through a period of change.
The latest reorganisation of the Civil Service comes after Sir Bob Kerslake announced his plan to step down as head of the Home Civil Service in the autumn.
Downing Street's top official - Cabinet Secretary Sir Jeremy Heywood - will take on Sir Bob's role while the new chief executive will have three key roles and will report to Sir Jeremy "in management terms".
Sir Jeremy has been forced to deny that David Cameron's decision to effectively reverse the reforms he implemented in 2011 was "management by chaos".
The changes tear up the reforms introduced by Mr Cameron in 2011, when he split the roles of Cabinet Secretary, head of the Home Civil Service and permanent secretary at the Cabinet Office on the retirement of Sir Gus O'Donnell - now Lord O'Donnell - but Downing Street has rejected suggestions that it was a sign that the previous changes had failed.
The chief executive's first main task will be exercising control over commercial aspects of the Civil Service and managing the Government's efficiency and reform programme. They will be answerable to Parliament in these areas.
The CEO will also work "closely" with the Cabinet Secretary to challenge top mandarins from Government departments to ensure that the Government's reforms are implemented "with pace and rigour".
The successful candidate will also act as the senior permanent secretary responsible for driving the efficiency programme, sitting on the Civil Service Board and attending Cabinet as an observer.
The job description states that the new chief executive will be accountable ultimately to the Prime Minister, while working day to day with the Cabinet Office Minister, currently Francis Maude, and with the Chief Secretary to the Treasury, currently Danny Alexander, on "efficiency issues".
As well as highlighting private sector experience at a large company, the job description states the new CEO will need to have a "strong personal impact" and be able to persuade and negotiate.
They will also need a "keen awareness of the political and media context of the role and the differences between operating in the private and public sectors".
Pay is expected to be between £180,000 and £200,000 and applicants need to submit a CV, a maximum three page supporting statement and a statement of potential conflicts of interests.
The new chief executive is expected to start the job on November 1.
The Institute for Government said the new role will not be that of a traditional chief executive, instead proving more modest in responsibilities.
The think-tank also criticised the "rush" in the appointment - with only 10 days between the closing date for applications, on September 5, and final interviews on September 15.
Peter Riddell, Director at the Institute for Government, said: "The job description for the newly created position of chief executive of the Civil Service shows that the new role will not be a chief executive in any sense normally recognised in either the private or public sectors.
"The holder of the new post will not be responsible for either running the Civil Service or line managing Permanent Secretaries. The role, while important, will be more modest - in control of the commercial, supplier management, digital, property, HR, project management and civil service reform functions in the Cabinet Office to help drive forward change in departments across Whitehall.
"The new post will have multiple masters and accountabilities, to the Cabinet Secretary in support of his role as Head of the Civil Service, as well as, on a day to day basis, to the minister for the Cabinet Office.
"Moreover, the appointment is being rushed. There is only a fortnight between the closing date for applications and final interviews, and the proposed start is only six weeks later - a far more compressed timetable than would be normal for a senior corporate leader in the private sector."