The work is composed of four parts, each with a short introductory statement, respectively titled “The roots of government” (治本), “The substance of government” (治體), “Tasks to implement” (應事) (the longest part), and “Dealing with people” (接人), comprising a total of 35 sections (目) and 728 entries (條). Li Zhongzhuan’s pref. compares its intention (意) to that of Zhen Dexiu’s Zhengjing (q.v.), and its structure (體) to that of Zhu Xi’s Xiaoxue. The short entries consist of discussions, admonitions, and anecdotes on past officials culled from the classics, histories, and philosophers. In his own pref., Yang Yu compares his compilation to the mirrors into which people look to improve their appearance: in this case the mirror is what the ancients show us, and what needs to be improved is government. Every aspect of a local official’s career, behavior, and functions is covered. Yang prepared the work while an instructor (教諭) in the Longnan 龍南 (Jiangxi) county school during the years 1526-33. In late 1533 or early 1534 he submitted a copy to Tang Zhou 唐胄, who was serving as military superintendent (提督軍務) in the area and had just been informed of his transfer to Shandong. Yang was likely hoping for help to get the work published. He explained in his letter to Tang that there had been few books available when he worked on it and that he had just had an opportunity to add material from the Song (see Changting 長汀 XZ [1782], 25/32b). But the manuscript languished until Li Zhongzhuan was appointed assistant prefect of Tingzhou (Fujian), where Yang was now living as a retired official. Li states that, had he known the work earlier, he would not have printed his own Xunliang huibian (q.v.), a similar compilation; he insisted that Yang’s com­pilation, which had remained unpublished for twenty years, should be collated and published, so that present-day officials wishing to benefit from ancient examples might have a “true mirror” (真鑑). In his own pref., the author modestly claims he was keeping the text for his own use in case of a new appointment.