Prof. M. Viswanathan has been acknowledged as the "Father of Diabetology" in India. His impactful contributions throughout his career significantly advanced diabetes treatment and research. Published over 200 studies in renowned national and international journals, he played a pivotal role in enhancing India's standing in the global diabetes research and treatment arena. After completing his medical education at Stanley Medical College in Madras and obtaining his degree in 1946, he served as a house physician. In 1948, he pioneered India's first organized diabetic clinic at Stanley Medical College, a time when diabetes was not yet recognized as a separate field of study. Prof. Viswanathan's vision led to the founding of the Diabetes Research Centre in 1972, a non-profit dedicated solely to research. As its Founder Director, his passion, commitment, and leadership skills were instrumental in driving the centre's remarkable development. The centre gained recognition from the Indian Council of Medical Research (ICMR) in 1975 and from the Department of Science and Technology, Government of India, in 1983, marking significant milestones in its journey towards excellence in diabetes research. Renowned diabetologists Dr. V. Mohan and Dr. Vijay Viswanathan are his sons, and Dr. A. Ramachandran is his son-in-law.