Force accretion of the Armed Forces is an ongoing process dictated primarily by capabilities to be achieved, threat perceptions, prevailing external strategic security environment and emerging technologies.  The force accretion programme is being pursued in accordance with the Long Term Integrated Perspective Plan and the 12th Defence Plan (2012-2017).

Source: http://90paisa.blogspot.in/2013/12/latest-strength-of-indian-armed-forces.html