Battalion Aid Station Operations Medical evacuation of wounded patients begins at the unit level. The "combat medic" is the first individual in the Health Service Support chain who makes medically substantiated decisions based on medical MOS specific training. Since Army divisions do most of the actual fighting, it is important that unit and division level medical evacuation support overlap from the far-forward Battalion Aid Station (BAS) to the Division rear boundary. Battalion Aid Stations and Division Treatment Stations must operate in close proximity to enemy action; therefore, the medical personnel who work in these areas will often find themselves treating and evacuating patients under direct fire. A key element in the medical system is the need for responsive and rapid patient evacuation to ensure that evacuation. Proficient AMEDD NCOs/Officers are the key figures in mission success.