Dr Viswanathan had earlier worked as Deputy Head (Climate Change and Development) at the Embassy of Switzerland in India. Before that, he had worked as the Senior Adviser of Swiss Agency for Development and Cooperation (SDC), Joint / Additional Commissioner at the Ministry of Agriculture Govt of India, and Principal Director of Defence Research and Development Organisation. He is a veterinarian by training with a Masters in Veterinary Sciences and MBA. Dr Viswanathan was awarded the VISHIST SEVA MEDAL by the President of India in 1985 for the service to Defence of the highest order.