As Tony Blair attempts to beat Frank Sinatra's record for the number of farewell gigs achieved by one man, two people have judged that the time is right to give us their perspective on life at Number 10. Alastair Campbell's book comes out this summer. Since Campbell is an accomplished journalist and a diehard Blair loyalist, I don't expect more than hagiography - the study of saints - peppered with some entertaining attacks on his many foes.Of far more interest is Sir Michael Barber's book, Instruction to deliver - Tony Blair, public services and achieving targets, published this week. Barber was head of the prime minister's delivery unit between 2001 and 2005. Extracts previewed in The Times provided a tantalising glimpse of life at the centre of power. He describes the skills needed to stay within the orbit of 'the influence that unlocks Whitehall' - only demanding access to Blair when he really needed it, never wasting his time and always remaining focused on delivering the prime minister's priorities 'all day, every day'. It ensured Barber's survival in the inner-sanctum for four years while other advisers, 'tsars' and experts fell by the wayside. Lose Blair's confidence, he says, and 'the game was up'. He also articulates the frustrations of trying to deliver an enormous agenda for change when much of the power lay in the spending departments. It is a situation as familiar to any chief executive or leader as it is to future prime ministers. Barber has now joined management consultancy McKinsey, and his advice to the next prime minister is to establish a Department of the Prime Minister and the Cabinet (incorporating No 10 and the Cabinet Office) to continue to drive public service reform. 'No 10 is small and the spending departments are very big. If you tried to do it all, you'd become a completely mad control freak,' he says. Existing completely mad control freaks, take note.Barber's strategy was 'gentle pressure, relentlessly applied'. For example, he describes how, in 2002, the prime minister decided that proposals on tackling street crime were not radical enough. Blair demanded a meeting of Cobra, the emergency committee, likening the street-crime 'epidemic' to crises like foot and mouth. The result was a concerted campaign to shift police officers on to street crime as a priority. Barber describes how the weekly data 'finally began to shift steadily and substantially in the right direction'. Ironically, this extract from his book appeared on the same day as a speaker at the Police Federation conference criticised performance targets for forcing officers to make ludicrous arrests for offences as trivial as kids throwing cream buns in the street. Gordon Brown is in the bizarre position of touring the country himself, making promises to tackle deep-seated problems like the state of the health service and the shortage of affordable housing. We are expected to believe that he has suddenly become aware of these problems despite being a member of the Cabinet and holding the purse strings for the past decade. Brown is in the process of reinventing himself, and with it the approach to public service reform. As Blair was famous for saying, 'no change is not an option'. At the moment Brown is making soothing noises about listening and devolving responsibility. Once at No 10 he'll face even more frustrations in driving public service reform than Blair, with a less-forgiving public. Something tells me we can soon expect another raft of new performance targets.Perhaps that's why John Reid's security guard told him recently that, in the event of the home secretary getting shot: 'If you go down, I'm going down with you. I couldn't face the paperwork, sir.'