The elite Central Committee of China's ruling Communist Party holds a closed-door meeting from Saturday to Tuesday to set the country's economic agenda for the next decade.
Senior leader Yu Zhengsheng has said the plenum will unveil "unprecedented" reforms and Premier Li Keqiang has talked of "comprehensively deepening reform."
Here are some key facts about the plenum and how it works.
* The meeting is the third time that China's 205-member Central Committee has gathered since last November's leadership change, which ushered in Xi Jinping as party and military chief. Historically, such meetings, known as third plenums, have been a springboard for economic change in China. The Central Committee is the largest of the party's top decision-making bodies.
* To prevent leaks, plenum attendees are traditionally confined to the venue for the duration of the meeting.
* Little, if any, news of the proceedings is made public until it closes. Foreign media and most Chinese reporters are given no access.
* On the day the plenum closes, the official Xinhua news agency will issue a long dispatch giving details of what was agreed. To portray party unity, there will be no mention of any disagreements.
* Past plenums have been held under tight security at the Soviet-era Jingxi Hotel in western Beijing. Details have not been announced for the location of the November 9-12 plenum.
* The focus of this plenum is widely expected to be on economic reform, though there could be mention of social and political issues such as corruption, the environment and China's strict family planning rules. Western-style political reform is almost certainly not going to feature.
* The mood at plenums can vary greatly, depending on the agenda. A watershed conclave in 1978 overseen by Deng Xiaoping kick-started China's economic reforms, beginning the transformation of the world's most populous nation from a centrally planned backwater to an economic powerhouse.