Senior commander, or senior clone commander, represented the second-highest military rank a clone trooper commander could attain within the Grand Army of the Republic. These clone commanders were identifiable by the yellow flashes on their armor during the early stages of the Clone Wars, the conflict between the Galactic Republic and the Confederacy of Independent Systems. They oversaw large formations known as legions, which were also referred to as brigades, working alongside a Jedi General.
According to the Grand Army of the Republic's Order of Battle, the rank structure placed senior clone commanders below clone marshal commanders and above clone regimental commander. Examples of senior clone commanders include Senior Commander Gree of the 41st Elite Legion and Senior Commander A'den of the 7th Legion.
The rank of senior clone commander initially appeared in "Guide to the Grand Army of the Republic," a reference piece spanning eight pages. This article was authored by Karen Traviss and Ryan Kaufman and featured in the 84th issue of Star Wars Insider, a publication of IDG Entertainment. The issue was released on September 26, 2005.