All three branches of Pakistan armed forces, those are, Pak army, Pakistan air force and Pak navy have their SSG commando units. If you want to become a SSG commando, first you got to have regular commission in the Pakistan army and then after a service of 2-3 years you can volunteer for the Special Services Group (SSG). You have to appear in the selection test (which is a physical one-tough) and then you land in SSG school for OACC (officers advance commando course). 9 months of unbearable training and then you get the most prestige SSG wing to put on your uniform. In short it is said that only the people damned by their mothers join the Pakistan SSG!
You need to get into the army, serve in any normal regiment for 2 years(maybe its 3 now) before you can apply for the SSG. Selection for a Special Services Group commando is very tough and all those who apply are very determined as it is. And SSG training itself is simple madness.Only adrenaline junkies join up anyway (whether they know it themselves or not)
To be very specific the officers have to apply for the SSG selection. GHQ decides on who will get out there to test out (you need to have a couple of other approvals prior to the General Head Quarters approval). Then you get out there. You go through a bunch of tests and then after your selection, you go through the basic SSG course. All ranks go through the basic course, but only officers and some select Junior Commissioned Officers after completing the basic course go to the advanced course. So the officers training is much more rigorous in the SSG than that of the other ranks.
For Joining SSG, the merit is very high and the ‘cream’ of officers from Army are selected for the SSG. An officer that has 5 years of experience in serving Pakistan Army then be selected on high merit from within the units