Lieutenant General Nagaraj was commissioned into the Infantry of the Indian Army in 1965. He studied in King Georges School (now Rashtriya Military School) Bangalore. He is an alumnus of the National Defence Academy, Defence Services Staff College, where he also served as an Instructor and National Defence College.  Lieutenant General Nagaraj participated in the Indo-Pak wars of 1965 and 1971. He also has rich experience in counter-insurgency / counter militancy operations in Sri Lanka, North-East, Punjab and Jammu and Kashmir. As General Officer Commanding-in-Chief of Army Training Command, he promulgated the Indian Army Doctrine in 2004. General Nagaraj later raised and operationalised South-Western Army Command. He is the recipient of the Uttam Yudh Seva Medal and Param Vishisht Seva Medal.