Dr. Ajay Kumar, aged about 61 years, joined the Indian Administrative Service in 1985. He is a PhD in Business Administration from the Carlson School of Management, University of Minnesota. He also has M.S. in Applied Economics from the University of Minnesota. He did his B.Tech in Electrical Engineering from the Indian Institute of Technology (IIT), Kanpur.

Dr. Kumar served as Defence Secretary during the crucial period between August 2019 and October 2022. He is the longest serving Secretary in Ministry of Defence, where he also served as Secretary in Department of Defence Production.

Dr. Kumar is currently a distinguished Visiting Professor at IIT Kanpur and a non-resident Senior Fellow at Carnegie India. He is also Founder Chairman of Mounttech Growth Fund, a AIF Category - II Venture Fund. He has a monthly editorial in Business Standard titled "Off the Grid" in the areas of defence, strategy, technology and policy. He is also mentoring start-ups and industry in fields of technology and defence."