Book excerpt: Discreet, inconspicuous, prudent... The perfect prime-ministerial aide is always in the background, a low-profile figure unknown outside the Westminster bubble. Unfortunately, reality often falls short of the ideal; for as long as the office of Prime Minister has existed, its occupants have been supported by a range of colourful individuals who have garnered public interest, controversy and criticism. At Power's Elbow tells their story for the first time, uncovering the truth behind three centuries' worth of prime ministers and their aides. Its subjects range from the early media-managers and election-fixers of Sir Robert Walpole, to the teams supporting the wartime premierships of David Lloyd George and Winston Churchill, to the semi-official 'Department of the Prime Minister' established under Tony Blair. Along the way, Andrew Blick and George Jones demonstrate how these essential advisers can be a source of both solace and strife to their chiefs, solving and causing problems in almost equal measure. Above all, they reveal how a Prime Minister's approach to his staff can define his premiership, for better or for worse.