- "Order 4: In the event of the Supreme Commander (Chancellor) being incapacitated, overall GAR command shall fall to the vice chair of the Senate until a successor is appointed or an alternative authority identified as outlined in Section 6 (iv)"
- ―Grand Army of the Republic Contingency Order 4
The order was the fourth in 150 contingency orders programmed into the clone troopers' inhibitor chips. Like all the contingency orders, when delivered to the clones, they were to be executed without hesitation. Despite memorizing the orders, if the chip was removed, for cases such as Fives, Rex, Gregor and Wolffe, they would execute the order or not on their own personal accord.
The order's implications specified that if Supreme Chancellor Sheev Palpatine - the Supreme Commander of the Grand Army and an office occupied by Palpatine during the war - was incapacitated in such a manner as to prevent him from performing his duties, command of the army would temporarily fall to the Vice Chair of the Senate, a position at the time held by Mas Amedda. The Vice Chair would be relieved of his command once a new Supreme Chancellor was elected.
In 19 BBY, 995 days after the First Battle of Geonosis, Atin (Omega Squad) indirectly mentioned Order 4, along with the rest of the Grand Army's 150 contingency orders, to squadmate Corr and Jedi General Etain Tur-Mukan during a conversation at the Republic's Special Operations Brigade Headquarters on the galactic capital, Coruscant. However, Order 4 was never employed by the Republic during the Clone Wars.
- Republic Commando: True Colors
- Order 66: A Republic Commando Novel