A central committee is a political-executive organ designated as the highest organ of a communist party between two congresses. Per the principles of democratic centralism, a central committee is empowered to deal with any issue that falls under the party's purview. While formally retaining this role in socialist states, commonly referred to as communist states by outside observers, in practice, it delegates this authority to numerous smaller internal organs due to the infrequency of its meetings.

The term of a central committee of a ruling communist party is usually five years. The party congress elects individuals to the central committee and holds it accountable. At the first central committee session held immediately after a congress, it elects the party leader, an office usually titled general secretary of the central committee, a political organ, commonly known as the politburo, and an executive organ, customarily named the secretariat.

Status Communist parties are organised on Leninist lines based on the principles of democratic centralism. Adolf Dobieszewski, an official of the Central Committee of the Polish United Workers' Party (PUWP), tried to define democratic centralism in 1980. He posited that centralism involves unifying party building and policy to construct a socialist society. To achieve unity in party building and policy, Dobieszewski contended that the minority had to be subordinate to the majority. Secondly, he posited that lower-level organs were subservient to higher-level organs. Third, members willingly acquiesced to discipline, and political discipline was equally obligatory for all party members. Democracy, on the other hand, meant, according to Dobieszewski, that every member had equal opportunity to participate in the formulation of the party's programme and line, as well as the right to elect and recall officials at all levels.

Power was organised as a uniform structure, with the highest party organs, such as the congress, functioning as the party's "supreme organ". This supreme organ is responsible for electing the central committee, which is typically tasked with directing the work of the communist party in between two congresses. According to scholar Baruch Hazan, the former ruling Eastern European communist parties provided nearly identical descriptions of the functions and powers of their central committees. Their responsibilities included representing the party externally, organising party organs, directing their activities, nominating personnel for internal organs, evaluating party cadres, and administering internal funds. Additionally, they were responsible for overseeing the work of state organs, granting approval to the state plan and budget ahead of the discussions in the supreme state organ of power (SSOP), and endorsing the appointments of individuals to prominent state roles. However, more generally, central committees are empowered to deal with any issue that falls under the party's purview.

Relationship to the state

Most communist states formally enshrine the communist party's leading or guiding role in state and society, and this is institutionalised by giving the party two-thirds of the seats in the supreme state organ of power (SSOP), which has complete control over all state activities per the principle of unified power. These members are, in most cases, elected in non-competitive elections and stand as candidates on the approval of the central committee.

Many central committee members also serve concurrently as members of their nation's supreme state organ (SSOP). In the Soviet Union, 227 out of 241 members of the Central Committee of the 24th Congress of the Communist Party of the Soviet Union (CPSU) concurrently served in the Supreme Soviet of the Soviet Union. They tended to dominate the Supreme Soviet and occupied leading political positions within it. In 1971–1973, forty per cent of debate participants were either members or alternates of the central committee. Party members who serve in the supreme state organ are also bound by party discipline and have to enact policies approved by the central committee.

The leading role principle entails that the central committee adopts recommendations on state policy on behalf of the party to, most commonly, the supreme state organ (SSOP), but also to other state organs if deemed necessary. For instance, the Central Committee of the Hungarian Socialist Workers' Party (HSWP) "adopted recommendations for filling of jobs in the state apparatus" to Hungary's SSOP, the National Assembly, on 29 March 1979. In other instances, the central committee could instruct its members to resign from state offices. The 7th Session of the Central Committee of the 8th PUWP Congress, held on 1–2 December 1980, instructed Edward Babiuch, Jerzy Łukaszewicz, Tadeusz Pyka, Jan Szydlak, Tadeusz Wraszczyk, and Zdzisław Zandarowski to resign their seats in the Sejm, the SSOP in the People's Republic of Poland, and instructing its former leader, Edward Gierek, to resign from his seat in the State Council.

The central committee could also nominate individuals to state positions. On 11 April 1984, during the 1st Session of the 11th Supreme Soviet of the Soviet Union, Mikhail Gorbachev nominated Konstantin Chernenko as chairman of the Presidium of the Supreme Soviet of the Soviet Union "on instructions of the Central Committee". Upon his election, Chernenko nominated Nikolai Tikhonov as chairman of the Council of Ministers, the Soviet government, also on the instructions of the Central Committee. Moreover, Chernenko and Gorbachev both stated that the instruction had also been "approved by the party group" of the Supreme Soviet.

Marxist constitutional theorist Sylwester Zawadzki, and member of Poland's SSOP, the Sejm, defined the relationship between the party and state as follows, "The Marxist-Leninist party gives political direction to the work of both the [SSOP] and the Government. [SSOP] and Government both work to carry out a common program for building socialism. It does not mean, however, that under these conditions the importance of the [SSOP's] constitutional functions is reduced."

In practice, the party's central committee normally discusses and adopts the state plan and budget before the supreme state organ does. On 25 November 1981, the RCP Central Committee convened to discuss and adopt the state plan and budget. Two days later, on 27 November, the Romanian SSOP, the Great National Assembly, convened and adopted the central committee's proposals. Moreover, the speakers that spoke at the central committee sessions usually speak at the session of the SSOP. Very few debates occur during the SSOP session, and in most cases, these organs adopt the central committee's recommendations unanimously. This was not always the case. The Assembly of Yugoslavia rejected bills, the Polish Sejm voted against government appointments and, under Gorbachev's leadership, the Congress of People's Deputies and the Supreme Soviet regularly voted contrary to the wishes of the Soviet government and party leaders.

There have been several attempts to reform the relationship between the central committee and the SSOP. In China, according to scholar Anthony Saich, "the party cannot guarantee absolute support [in the SSOP] and has accepted a looser form of control than during the Maoist days when the National People's Congress (NPC) was simply stocked with model workers and peasants, pliant intellectuals and senior party leaders."

The first reforms were instituted in 1991, when the Central Committee of the Chinese Communist Party (CCP) adopted a regulation that limited the party's interference in the work of China's SSOP, the National People's Congress. The document clarifies that the CCP has the right to review all proposed laws, but detailed scrutiny of articles and other legal features should be left to the NPC.

In line with this, the number of negative votes by NPC deputies against proposed legislation and candidates has increased since 1991. The NPC has also rejected proposed legislation, such as the "Highway Law of the People's Republic of China" in 1999 and the "Property Law of the People's Republic of China" in 2006. In both cases, the proposed legislation was amended and passed at a later date.

In some cases, the central committee adopts decisions on behalf of state organs despite it not being in their jurisdiction. This occurred at a session of the Central Committee of the Communist Party of Czechoslovakia (CPCZ) on 13–14 September 1979 when it removed Jan Gregor, Frantisek Hamouz and Bohuslav Vecera from their government posts. Another example is the Extraordinary Plenary Session of Poland's PUWP Central Committee on 9 February 1981 that removed Józef Pińkowski, the sitting head of government, and replaced him with Wojciech Jaruzelski.

Organisation Sessions Ruling central committees normally can convene for three meeting types: sessions (also called plenums), extraordinary sessions, and joint sessions. These three types have two sub-forms: a closed session and an enlarged session in which non-members are invited to participate. Central committee sessions dealing with non-party issues are often enlarged, even if what is discussed is routine in nature.

These sessions are in most cases organised identically, and the key speech is often delivered by a central committee secretary responsible, for example, for economic affairs or international affairs. The discussions at the sessions are very seldom made public, but adopted resolutions are sometimes made public and session communiques are nearly always distributed to the public. In some instances, the number of non-members exceeds that of central committee members. The Romanian Communist Party (RCP) did this, and the Central Committee of the 12th RCP Congress convened an enlarged session on 1 June 1982 attended by 360 guests to discuss the "current stage of building socialism in Romania".

Sessions dealing exclusively with party affairs are usually closed. These sessions' most common agenda item is "organisational matters", meaning personnel changes in party and state organs. The communiques published by these sessions are usually brief and say little to nothing about the reason for the changes. But this was not abnormal. For instance, in East Germany, the official communique of the 13th Session of the Central Committee of the 7th Congress of the Socialist Unity Party of Germany (SED), held on 11–12 December 1980, only notes that two politburo members, Günter Mittag and Gerhard Schürer, spoke at the session, that fifteen central committee members participated in session discussions and that it approved the SED Politburo's report and the proposed economic plan for 1981.

The same rule regards extraordinary sessions, both ordinary and enlarged, as well. In some cases, these sessions were made public long after the fact. For example, the Central Committee of the Bulgarian Communist Party (BCP) reported that an "important" Central Committee session had taken place 1–2 July 1976, but only informed the public that "measures to ensure the consistent and all-round implementation of the decisions of the 11th BCP Congress" had been adopted and discussed. What these measures were was not made public. The importance of the session was indicated by the fact that Todor Zhivkov, the first secretary of the BCP Central Committee, "read a detailed report" to the session. However, the report's content was not made public either.