A gutsy agitationist and leader with mass appeal known for her humble lifestyle, the 54-year-old 'didi' of Kalighat in south Kolkata, becomes union minister for the fourth time.
Having risen through the ranks in the Congress, Banerjee made political analysts sit up and take notice of her in 1984 when she stunned Communist Party of India-Marxist (CPI-M) stalwart Somnath Chaatterjee from the Jadavpur constituency in her maiden Lok Sabha contest.
Banerjee quit the Congress in 1998, saying it had diluted its opposition to the CPI-M. She formed the Trinamool Congress, which soon dislodged the parent party to become the state's main opposition.
In her bid to strike the right arithmetic to oust the Communist-led Left Front government, Banerjee courted the Bharatiya Janata Party (BJP)-led National Democratic Alliance (NDA) from 1998 to 2001, supped with the Congress during the 2001 assembly polls and again dated the NDA from 2001 to 2006.
In the 2009 Lok Sabha polls, Banerjee joined forces with the Congress to defeat the communists.
Her earlier stints at the centre have mostly ended in controversies. In 1991 as minister of state for human resource development in charge of youth affairs and sports in the Narasimha Rao government, her innings was short-lived. She quit two years later, saying she wanted to be with the "oppressed" Congress workers.
In October 2001, Banerjee took over as railway minister, this time in the NDA government of Atal Bihari Vajpayee. However, she resigned 17 months later, over the Tehelka arms purchase controversy from which she wanted to distance herself and her party.
She again returned to the Vajpayee government as coal minister in January 2004, but her innings ended soon as the NDA was defeated in the elections.
With her eyes focussed on ending the 32-year-old communist rule in West Bengal, the seven-time MP is likely to utilise her tenure as minister to announce plum projects for the state to fight the 2011 assembly elections on the development plank.
