In 2004, she retired as the chairperson of Thermax Ltd, handing over the reins to her daughter Meher Pudumjee. Thermax is a Rs 4,935 crore engineering solutions provider in the energy and environment sectors.
She is also a member of the National Advisory Council, headed by Sonia Gandhi, which works closely with the central government on public policy and issues, such as the Right to Food.
In 2010, Aga was awarded the Padma Shri for her work in the social sector, where she has been involved with promoting communal harmony and nurturing education. She supports Akanksha, a non-governmental organisation that promotes school education for the underprivileged children in Mumbai and Pune.
She is also closely associated with the Thermax Social Initiative Foundation (TSIS). The foundation, in partnership with the municipal corporations of both cities and Akanksha, manages two schools for lower-income groups. She is also known for her to transparency in corporate governance.
Last year, Ms Aga was ranked No. 79 on Forbes magazine's Richest Indians list with a net worth of $655 million (Rs 3,440.7 crore, at current rates).
FROM TRAGEDY TO SUCCESS
Thermax was set up by her father AS Bhathena in 1966 as Wanson (India) to provide a range of engineering solutions. The company was renamed Thermax in 1980 after her father retired. Her husband, Rohinton, headed it till 1996, when he died of a massive stroke. While Ms Aga was still finding her feet as the head of Thermax, she suffered a second tragedy - her 25-year-old son Kurush was killed in a road accident.
Thermax's growth had nose-dived at the time, with share prices plummeting from Rs 400 to Rs 36 because of the market downturn.
Ms Aga has said that an anonymous letter from a shareholder accusing her of letting him down forced her to take stock of the situation. It dawned upon her that as the largest shareholder of a public limited company, it was her responsibility to turn the company around even if she personally felt she didn't deserve to be its chairperson.
She started a full-scale reform, with help from the Boston Consulting Group. Between February 1996, when she took over as chairperson of Thermax, and 2004, when she stepped down, Ms Aga transformed the company into a global turnkey player in energy and environment projects.
On Friday, Thermax shares were trading on the Bombay Stock Exchange at Rs 447.15, up 1.96 per cent, while the benchmark Sensex was down 0.36 per cent. .
Eight years after Ms Aga took the top post, her daughter Meher replaced her as head of the company. However, she continues to be on the company's Board of Directors.
Ms Aga graduated with a Bachelor's in Economics from St Xavier's College in Mumbai and has a post-graduate degree in medical and psychiatric social work from the prestigious Tata Institute of Social Sciences (TISS). She was also selected for a Fulbright Scholarship and studied in the United States for four months.
A PHILOSOPHY OF LIFE
In interviews, she has often been asked where she draws her strength from. According to Ms Aga, her husband often teased her for her incessant chatter. Now, she says, Vipassana, a form of meditation, helps in times of distress. "It required the rigour of maintaining silence," she said.
In an interview to Harmony, a magazine for senior citizens published by the Anil Dhirubhai Ambani group, Ms Aga said she prefers the 'early to bed and early to rise' routine. Her day, she says, starts with exercise, usually a mix of cycling, yoga and walking. She doesn't watch much TV, preferring to catch up instead with the news through newspapers.
Her favourite watersport is snorkeling, she told the magazine. "It is a whole new world under the sea."
In a television interview in May 2005, Ms Aga compared life and death to the rising and setting of the sun. She's negotiated with them being "life's natural processes", she said. What is non-negotiable, she pointed out, is her time with her grandchildren Zahaan, 9, and Lea, 6.