The Joint Staff assists the Chief, National Guard Bureau in the decision making and execution process of his mission. The sole function of the Joint Staff is command support, and its only authority is that which is delegated to it by the Chief, National Guard Bureau.

The Joint Staff assists the Chief, National Guard Bureau, in accomplishing his responsibilities for strategic direction of the National Guard forces; their operation under unified command; and their integration into an efficient team of land and air forces. The joint Staff is composed of Army and Air National Guard personnel, as well as Navy and Marine Corps forces. The Joint Staff acts as the Department of Defense channel of communication to and from the National Guard of the States and Territories.