Dr. Mashelkar’s research is in the area of transport phenomena; particularly in thermodynamics of swelling, super swelling and shrinking polymers, modelling of polymerisation reactors, and engineering analysis of non-Newtonian flows. He started his research career at National Chemical Laboratory in Pune, where he rose to become its Director. He also served as the Director
General of CSIR from 1995 to 2006--being one of the longest serving Director Generals of CSIR. He is credited with unifying the various laboratories of CSIR and striving for greater collaboration amongst different labs. 

One of his important contributions to the society is his legal crusade against US patents on turmeric, neem and basmati rice. This also led to recognition and need for stronger IP laws in the country, in addition to earning h im the title ‘the Warrior of Haldighati’. Dr. Mashelkar has received numerous awards including the Padma Vibhushan, Padma Bhushan and the Shanti Swarup  Bhatnagar Award. He has been elected to several academies and advisory councils across the world. He is the National Research Professor and Chairperson of the National Innovation Foundation.