Pei Yan
The chancellors periodically met together at the "Zhengshi Tang" (政事堂, literally "the Hall of State Matters"), originally physically located within the examination bureau. In 683, when Pei Yan, then the head of the examination bureau, became the head of the legislative bureau, the "Zhengshi Tang" was moved from the examination bureau to the legislative bureau. Later, during Emperor Xuanzong's reign, when Zhang Shuo became chancellor, he changed the name to "Zhongshu Menxia" (中書門下), apparently employing a double entendre, as when the terms were put together, they meant, "within the doors of the "Zhongshu"." Zhang also reorganized the Hall by creating five offices under the chancellors—in charge of civil service, state secrets, military matters, governance, and criminal law, respectively. Later in the dynasty—starting during the reign of Emperor Suzong — the chancellors begin to rotate off-days so that at least one would always be on duty; when submissions were to be made to the emperor, they were signed in the names of all chancellors, whether on duty or not. The name of their meeting place also changed back to "Zhengshi Tang".