The generals-and-troops law (jiangbingfa 將兵法), also called law on the creation of commands (zhijiangfa 置將法) was aimed at ameliorating the quality of high officials and their relationship to the common troops. The law was part of the reform politics of Wang Anshi 王安石 during the Northern Song period 北宋 (960-1126), but did actually not belong to his own reform agenda.
The conventional military units of the Song period were companies (du 都, 100 men), battalions (zhihui 指揮, 500 troops, also called ying 營), regiments (jun 軍, 5 zhihui, or 2,500 troops), and divisions (xiang 廂, 10 jun, or 25,000 troops). The Song army was afflicted by two problems, first, the understaffing of units (the number of troops did not reach the nominal size, while the funds were still paid out), and second, the mental distance between high officers and common troops. Fan Zhongyan 范仲淹 had therefore attempted to restructure the military units in a test phase in the circuit of Luyan 鄜延 (today in Shaanxi), where he divided the 18,000 men strong divisions of the metropolitan army (jinjun 禁軍) into six commands (jiang 將) that were commanded, trained and organized by infantry and cavalry officers (XXX 分路都監, 駐泊都監). Cai Ting 蔡挺 carried out a similar project in the prefecture of Weizhou 渭州 and the circuit if Jingyuan 涇原. His commands were much smaller (2,500 troops) and consisted of ten companies (chen 陳, 125 troops), and the latter of platoons (dui 隊, 25 troops). Most important is that the commands consisted of a mixture of infantry and cavalry units, as well as archers and frontier tribal troops (fanbing 蕃兵).
This pattern was in 1072 extended to the whole country, but the commands were divided into bu 部 and dui (50 troops). There were finally between 92 and 140 commands in the Song empire, with a size per command of between 3,000 and more than 10,000 troops. The staff of a command was headed by a general (zhengjiang 正將) and a lieutenant general (fujiang 副將). The units under the command understood *colonels (bujiang 部將) and *majors (duijiang 隊將), as well as commissioners (yadui shichen 押隊使臣) and training officers (xunlianguan 訓練官). The selection of officers was carefully implemented, to promote just the most qualified.
The system was used for all units, barring the palace and metropolitan units. This structure was quite successful for the coherence of military bodies and the training of troops, and was therefore continued until the end of the Southern Song period 南宋 (1127-1279).