Since leaving Downing Street more than two years ago, Sarah Brown has devoted herself to charity campaigning, raising two young sons, John and Fraser, and writing a book about life at No 10.
Now Mrs Brown, who as Sarah Macaulay co-founded the successful public relations agency Hobsbawm Macaulay Communications when she was 30, has returned to the world of business, joining luxury department store Harrods as a non-executive director.
The famous emporium is no longer owned by the flamboyant Mohamed Al Fayed, but is in the hands of a Qatari-owned business.
Mrs Brown will advise Harrods on developing marketing plans, including corporate social responsibility programmes.
The store said the 50-year-old would draw on her extensive experience across a range of businesses and not-for-profit organisations.
According to documents filed at Companies House, Mrs Brown describes herself as a charity director and writer.
She said: "I look forward to my return to business in joining the Harrods Group board and welcome the opportunity to work on the marketing and corporate social responsibility plans for this world-renowned British brand."
Mrs Brown was born in Buckinghamshire to schoolteacher mother Pauline and Scots-born father Iain, who worked for the Longman publishing company, and spent some of her early childhood in Fife.
She also lived in Tanzania with her parents for a spell but settled with her mother in London at the age of seven following her parents' divorce. After graduating with a psychology degree from Bristol University, Mrs Brown worked at brand consultancy Wolff Olins specialising in Labour events, such as the Manufacturing Matters Conference and party donor events.
She then co-founded the PR firm Hobsbawm Macaulay with schoolfriend Julia Hobsbawm.
She first met her future husband at a Labour Party event her firm was organising, and they married in 2000 in a Church of Scotland ceremony at the then Chancellor's North Queensferry home.
She left work a year later when expecting daughter Jennifer Jane, who died at 10 days old after being born two months prematurely in hospital in Kirkcaldy.
In a series of essays for a charity book, she described how much the tragedy had changed her life.
Mrs Brown wrote: "I had assumed I must find a way to recover and resume my life, which proved impossible. Instead I realised that the loss of Jennifer had changed me forever, and importantly I realised that this was OK."
Qatar Holding acquired the Harrods group for £1.5 billion in 2010.
It is unclear how much Mrs Brown will be paid or how many days she will dedicate to her role.