The Commanding Officer and founder of HOD is HOD-Leader.
HOD-3 is responsible for the financial administration and cares for everything concerned with personell like salary payment, organization of leaves, recruitment of needed personell etc. and Public Relations.
HOD-2 is concerned with military intelligence (knowledge about enemy units, theis tactics etc.) and security issues regarding HOD (counter-intelligence as well as guarding the property of the unit).
In case the C-in-C is incapacitated HOD-4 takes over command of the unit.
HOD-3's duty additionally to that of S1-Officer is the managment of all activities and the organizational needs of supply and maintenance. He is the supervisor of all support personell (like Techs) HOD employs.