The Tang system of bureaucratic titles was complicated. A high-ranking official, for instance, might simultaneously hold four sets of titles: the first indicated his substantive office, the second his nominal rank in the officialdom, the third his military merits, and the fourth his enfeoffment. After the An Lu-shan安祿山rebellion, yet another set of bureaucratic titles was introduced, the so-called Jianjiao檢校title. It was first bestowed as a “friendly” gesture or reward on powerful rebel generals who surrendered to the Tang court in the last phase of the rebellion. Later, it became institutionalized and was routinely given, for the most part, to high-ranking and mid-level officials stationed under various civil and military commands in the provinces. Thus, a mid-level provincials official such as an Executive Officer (Panguan 判官)might be given the title of Secretary of Personnel (Libu langzhong吏部郎中), a min-level substantive office in the central government in the capital. However, in such cases, the prefix Jianjiao would be added to indicate that this office was merely supernumerary, and that its holder would not be added to indicate that this office was merely supernumerary, and that its holder would not be required to serve concurrently in the capital. Such Jianjiao titles can frequently be found in min and late Tang documents, as well as in epigraphic sources, causing much misreading, misunderstanding, and mis-representation. Yet not a single in-depth study has been done on this subject. Many Chinese-language looks on Tang history have failed to take into account this relatively new set of Jianjiao titles. This paper is the first attempt in any language to explore its origins, its sues, and its significance in the Tang bureaucracy.