Secret court letters (tingji 廷寄, also called jixin 寄信 or jixin yuzhi 寄信諭旨 "letter edicts") were imperial orders to high functionaries of the central or local government not promulgated in public. The early Qing dynasty 清 (1644-1911) inherited the practice of the Ming dynasty that all imperial orders were made public through the Grand Secretariat (neige 內閣), which passed on orders to the institutions in question. Yet this practice was not acceptable for orders that required confidentiality. Moreover, the way through the Grand Secretariat took some time.
The Kangxi Emperor 康熙帝 (r. 1661-1722) therefore began to send confidential orders concerned with the duties of high state officials, military affairs, issues of the Censorate or penal matters directly to the institutions in question, with the help of central-government officials, princes or Grand Academicians (daxueshi 大學士). In 1729, the Yongzheng Emperor 雍正帝 (r. 1722-1735) created the State Council (junjichu 軍機處) as the central policy-making body. Confidential orders were from then on one of the duties of the members of the State Council.
The formal shape of secret court letters depended on the recipient. The formula "sent in the name of the members of the State Concil" (junji dachen ziji 軍機大臣字寄) was used for orders to members of the State Council acting as Grand Ministers Commander (jinglüe da jiangjun 經略大將軍), Grand Ministers Inspector-General (qinchai dachen 欽差大臣), general (jiangjun 將軍) or Grand Ministers Consultant (canzan dachen 參贊大臣), to Banner commanders-in-chief (dutong 都統) and vice commanders-in-chief (fu dutong 副都統), to Grand Ministers Superintendant (banshi lingdui dachen xxx 辦事領隊大臣), governors-general (zongdu 總督), provincial governors (xunfu 巡撫), provincial educational commissioners (xuezheng 學政) and administrator xxx 督辦軍務大員等，. The formula "edict passed on by the members of the State Council" (junji dachen chuanyu 軍機大臣傳諭) was used for Grand Ministers of salt administration (yanzheng 鹽政), customs collectors (guanchai 關差), xxx 藩、臬及各省提鎮等，用“軍機大臣傳諭”；For very important matters, the formula "secretly sent in the name of the members of the State Council" (junji dachen miji 軍機大臣密寄) was applied.
The first page of the secret letter listed the family names and ranks of the members of the State Council, but only until 1797, whereafter the summary formula junji dachen ziji was used. The compilation of a secret letter began with the sovereign's order to write a draft, which was then presented to the ruler as "narration of an imperial order" (shuzhi 述旨). The sovereign then read and revised the draft, and had it sealed by the State Council and expedited in a closed envelope (fenghan 封函). The envelope was sealed and inscribed with the words xxx “辦理軍機處封寄某處某官開拆” or “傳諭某處某官開拆”, and—depending on the urgency—the distance the letter had to pass in one day (in other words, the velocity of delivery along the imperial courier routes). The expedition was organized by the Ministry of War (bingbu 兵部). 書“軍機大臣字寄某官開拆”或寫上“傳諭某官開拆”。
Only the recipient in person was allowed to read the document. He had also to confirm in his answer the time of reception and the name of the presenter, as well as how he would deal with the imperial order. In case the secret letter was addressed to a functionary of the Imperial Household Department (neiwufu 內務府), it was to be dispatched in the name of one of the Grand Ministers Supervisor (zongguan dachen 總管大臣) of the Department.
A similar type of secret court letter, called mingfa 明發 "lucid disclosure or mingfa yuzhi 明發諭旨 "edict of lucid disclosure", was used concerning a different range of issues, namely imperial inspection tours, visits of the ancestral tombs of the dynasty, colloquia on the Classics (jingting 經筵), tax waivers (juanzhen 蠲賑) or awards, punishments, dismissals and transfers of high functionaries.