Ghanashyam Das Birla, Walchand Hirachand Doshi, Kasturbhai Lalbhai and Jeha-ngir Ratan Dadabhoy Tata were the four pioneers who came to head India's industrial surge of 1951-62 because of their nationalism and vision. Gita Piramal, India's leading chronicler of business history, has delved deep into the background of four of the oldest corporate groups to find out why they are legends.