清乾隆朝官修的“续三通”，即《续通典》《续通志》《续文献通考》，是典制体通史“三通”（《通典》《通志》《文献通考》）的续作，因而其所记述的内容也成为典章制度通史体系中的一部分。

“续三通”的纂修，出自乾隆帝的指示，具体工作先后由“续文献通考馆”“三通馆”承担。“续三通”继承了“三通”会通古今、事类相从的编纂方法，并在资料搜辑、事类排比等方面有较多的补充或改进。在贯通唐代至明代典章制度史的过程中，“续三通”基于大一统、历史文化认同和以史为鉴的编纂理念，对自上古三代以来的制度变迁轨迹和制度理念进行了重塑，并在制度的叙述和评论中多将其与清朝制度相对比，以体现清朝制度对中华制度文明的继承和发展，建构清皇朝及其政治理念的正统性。乾隆帝亲自审读书稿，纠正讹误，甚至规定某些事件的评论尺度，是为“续三通”的重要特点。其体例在依循“三通”的基础上，因所载历史时段的特殊情况、馆臣的政治立场及学术理念而相应变通。书中的史论，除仿照“三通”采诸家之说外，还参考或直接照搬了乾隆帝的“御批”。

“续三通”虽是记载前朝制度，但往往展现出清朝制度的立场。乾隆君臣在对边疆与外国界限认识逐渐明晰的情况下，依然按照前朝史家的视角叙述“四裔”，并与清朝疆域对比，目的是展现清朝空前的“大一统”格局。而在礼制史的撰述中明确尊卑等级，是为了巩固皇权的独尊地位。对比当时所撰本朝制度史，“续三通”明显更注重历代制度的继承性，在体例上也更趋近于“三通”。

“续三通”在记述历代制度的同时，也总结和提出了关于制度的思想。乾隆君臣认识到制度施行日久就会滋生弊端，因而重视制度的因时变通。在继承中原历代皇朝制度传统的同时，乾隆帝也强调保持本民族的固有制度，但最终目的却是强化清皇朝的治统。在前代制度史的编纂之中，乾隆君臣表达了对于历代相传的制度传统的理解和认同，这是清朝统治集团认同并继承中华文明的深刻体现。

The "Xu Santong"（“续三通”） officially compiled during the Qianlong period of the Qing Dynasty, namely Xutongdian（《续通典》）, Xutongzhi（《续通志》） and Xuwentongkao（《续文献通考》）, are the continuations of the "Santong"（“三通”） of the general history of the institutions, so the content of its description is also become part of the general history of institutions.

The compiling method of "Xu Santong" is to connect various eras and classify events. The compiling concept is useful for real politics. At the same time, it is deeply influenced by the political background of "Dayitong"（“大一统”） and the academic atmosphere that pays attention to textual research in the Qianlong era.　Emperor Qianlong personally reviewed the manuscripts, corrected corruption, and even stipulated the scale of comments on certain events, which is an important feature of "Xu Santong". On the basis of following the "Santong", its style is adapted accordingly due to the special circumstances of the historical period contained in it, the political positions and academic ideas of the officials. The historical comments in the book, in addition to collecting many viewpoints imitating the "Santong", also refer to or directly copy the "Royal Appraisal" of Emperor Qianlong.

Although the "Xu Santong" record the system of the previous generation, it often shows the position of the contemporary system. As Emperor Qianlong and his ministers gradually became clear about the boundaries between frontiers and foreign countries, they still described the "Dayitong" from the perspective of historians of the previous dynasty, and compared them with the territory of the Qing Dynasty, in order to show the unprecedented pattern of "great unification" of the Qing Dynasty. In the writing of the history of ritual system, the rank of honor and inferiority is clearly defined in order to consolidate the exclusive status of the imperial power. Compared with the contemporary institutional history written at that time, the "Xu Santong" obviously paid more attention to the inheritance of the systems of the past dynasties, and was closer to the "Santong" in terms of style.

"Xu Santong" not only described the system of the past dynasties, but also summarized and put forward the theory on the system. Emperor Qianlong realized that the long-term implementation of the system would lead to malpractices, and therefore emphasized that the system should be adapted from time to time. While inheriting the institutional traditions of successive dynasties in the Zhongyuan（中原）, it also pays attention to maintaining the inherent system of the nation, but the ultimate goal is to maintain and consolidate the rule of the Qing Dynasty. In compiling the institutional history of previous generations, Emperor Qianlong and his ministers　expressed their understanding and recognition of the institutional traditions passed down through the ages, which is a profound manifestation of the Qing Dynasty ruling group's recognition and inheritance of Chinese civilization.