Sir Dorab Tata, aided by his cousin R. D. Tata, saw group founder Jamsetji Tata's projects through to the stage of accomplishment. The additions during his leadership were an integrated steel plant, then the largest single unit in the British empire, three hydroelectric power companies, a large edible oil and soap company, two cement companies and an aviation unit pioneered by JRD Tata.

Sir Dorab also saw through the establishment of the Indian Institute of Science, Bangalore, which was to spearhead scientific research in India for decades to come. He was knighted in 1910.

Sir Dorabj's love of sport was abiding. He had the country scoured for sports talent and brought India into the Olympic movement. As president of the Indian Olympic Council, he financed the Indian contingent to the Paris Olympiad in 1924.

Sir Dorab always believed that wealth must be put to constructive use. Towards the end of his career, in 1932, he put all his wealth — including the 245-carat Jubilee Diamond, twice as large as the famed Kohinoor and estimated to cost Rs 1 10 million then — into a trust for the advancement of learning and research, the relief of distress and other charitable purposes. This was the beginning of the Sir Dorabji Tata Trust.

The Lady Tata Memorial Trust for research in diseases of the blood was also promoted by Sir Dorab.