Sanggung

was an official title of the senior 5th rank (; ), the highest attainable for palace ladies during the Joseon period. Female officials with the title were assigned to govern the inner affairs of the palace. When a regular nain served for more than 15 years, she would be awarded with an ornamental hairpin for a . Therefore, a newly appointed was usually 35–45 years old. A court lady at the rank of was treated well enough to live in her own house with servants.

The title first appears in Goryeosa ('History of Goryeo'), a compiled book about the Goryeo period. In the chapter of the book titled , regarding all official titles, there were posts named (, managing the palace), (, managing bedding), ( managing food), and another (, managing sewing) during the reign of King Hyeonjong. The book also has another record that Lady Han was appointed as in March 1031, the 22nd year of the king's reign. These records prove that the system had existed since the Goryeo period.

As a system on Naemyŏngbu which refers to women at court with a rank including queen and lady-in-waiting was revised since the start of the Joseon period, female officers with the title, began to manage inner affairs of the court in general as the highest position of the (literally a palace officer). The was largely divided into (literally 'internal offices' ) and according to Kyŏngguk taejŏn. The former refers to a king's concubines or a crown prince's consort while are female officers with a rank. They had the highest position among , and they were responsible for the management of properties. They served the king with many other ladies-in-waiting in his palace, received the king's orders and held political power. – also called ; they managed the properties in the warehouse of the palace. – also called ; they waited closely on the king. – literally 'a nurse '; they took care of the princes and princesses. – literally 'a maid-in-waiting '; they assisted with books and ceremony. – literally 'an inspector '; they inspected and gave out punishments to .