 A year later, he took up the position of the director general of the Indian Council of Medical Research.After retiring from ICMR in 1974, he worked at Sir Ganga Ram Hospital as a consultant pathologist till 1984.He wrote over 300 medical articles and books, including "Histological Typing of Oral and Oropharyngeal Tumours", a book written for the World Health Organization, and has mentored several research scholars in their doctoral studies.