[1] A member of the Labour Party, he was chief strategist to Gordon Brown during his tenure as Prime Minister and Chancellor of the Exchequer.

Prior to the 2007 Budget, Livermore reportedly advised against Brown's decision to abolish the 10p income tax rate.

Responsible for strategic planning and attending Cabinet meetings, he devised the strategy for the Prime Minister's transition and first 100 days in office.

Livermore unsuccessfully advocated for a General Election in Autumn 2007, writing the initial strategy memo to the Prime Minister on the matter.

[4][5] Livermore reportedly declined an offer from Peter Mandelson to become Downing Street Chief of Staff, and a request from Gordon Brown to work on Labour's 2010 general election campaign.

[17][18] He is married to Seb Dance, a former Labour Member of the European Parliament now serving as Deputy Mayor of London for Transport.