The Executive and Legislative branches operate primarily at the national level, although various ministries in the executive branch also carry out local functions. Local governments are semi-autonomous, and contain executive and legislative bodies of their own. The judicial branch operates at both the national and local levels. The South Korean government's structure is determined by the Constitution of the Republic of Korea. This document has been revised several times since its first promulgation in 1948 (for details, see History of South Korea). However, it has retained many broad characteristics; with the exception of the short-lived Second Republic of South Korea, the country has always had a presidential system with a relatively independent chief executive.
As with most stable three-branch systems, a careful system of checks and balances is in place. For instance, the judges of the Constitutional Court are partially appointed by the executive, and partially by the legislature. Likewise, when a resolution of impeachment is passed by the legislature, it is sent to the judiciary for a final decision.
At the national level, the legislative branch consists of the National Assembly of South Korea. This is a unicameral legislature; it consists of a single large assembly. Most of its 300 members are elected from single-member constituencies; however, 56 are elected through proportional representation. The members of the National Assembly serve for four years; in the event that a member is unable to complete his or her term, a by-election is held. The National Assembly is charged with deliberating and passing legislation, auditing the budget and administrative procedures, ratifying treaties, and approving state appointments. In addition, it has the power to impeach or recommend the removal of high officials.
The Assembly forms 17 standing committees to deliberate matters of detailed policy. For the most part, these coincide with the ministries of the executive branch.
Bills pass through these committees before they reach the floor. However, before they reach committee, they must already have gained the support of at least 20 members, unless they have been introduced by the president. To secure final passage, a bill must be approved by a majority of those present; a tie vote is not sufficient. After passage, bills are sent to the president for approval; they must be approved within 15 days.
Each year, the budget bill is submitted to the National Assembly by the executive. By law, it must be submitted at least 90 days before the start of the fiscal year, and the final version must be approved at least 30 days before the start of the fiscal year. The Assembly is also responsible for auditing accounts of past expenditures, which must be submitted at least 120 days before the start of the fiscal year.
Sessions of the Assembly may be either regular (once a year, for no more than 100 days) or extraordinary (by request of the president or a caucus, no more than 30 days). These sessions are open-door by default, but can be closed to the public by majority vote or by decree of the Speaker. In order for laws to be passed in any session, a quorum of half the members must be present.
Currently, four political parties are represented in the National Assembly.
The executive branch is headed by the president. The president is elected directly by the people, and is the only elected member of the national executive. The president serves for one five-year term; additional terms are not permitted. The president is head of government, head of state, and commander in chief of the South Korean armed forces. The president is vested with the power to declare war, and can also propose legislation to the National Assembly. He or she can also declare a state of emergency or martial law, subject to the Assembly's subsequent approval. The President can veto bills, subject to a two-thirds majority veto override by the National Assembly. However, the president does not have the power to dissolve the National Assembly. This safeguard reflects the experience of authoritarian governments under the First, Third, and Fourth Republics.
In the event that they are suspected of serious wrongdoing, the president and cabinet-level officials are subject to impeachment by the National Assembly. Once the National Assembly votes in favor of the impeachment the Constitutional Court should either confirm or reject the impeachment resolution, once again reflecting the system of checks and balances between the three branches of the government.
The Cabinet (국무회의, 國務會議, gungmuhoeui) is the highest body for policy deliberation and resolution in the executive branch of the Republic of Korea. The Constitution of the Republic of Korea mandates that the Cabinet be composed of between 15 and 30 members including the Chairperson, and currently the Cabinet includes the President, the Prime Minister, the Vice Prime Minister (the Minister of Strategy and Finance), and the cabinet-level ministers of the 17 ministries. The Constitution designates the President as the chairperson of the Cabinet and the Prime Minister as the vice chairperson. Nevertheless, the Prime Minister frequently holds the meetings without the presence of the President as the meeting can be lawfully held as long as the majority of the Cabinet members are present at the meeting. Also, as many government agencies have recently been moved out of Seoul into other parts of the country the need to hold Cabinet meetings without having to convene in one place at the same time has been growing, and therefore the law has been amended to allow Cabinet meetings in a visual teleconference format. Although not the official members of the Cabinet, the chief presidential secretary (대통령비서실장, 大統領祕書室長), the Minister of the Office for Government Policy Coordination (국무조정실장, 國務調整室長), the Minister of Government Legislation (법제처장, 法制處長), the Minister of Patriots and Veterans Affairs (국가보훈처장, 國家報勳處長), the Minister of Food and Drug Safety (식품의약품안전처장, 食品醫藥品安全處長), the Chairperson of Korea Fair Trade Commission (공정거래위원장, 公正去來委員長), the Chairperson of Financial Services Commission (금융위원장, 金融委員長), the Mayor of Seoul Special City (서울특별시장, 서울特別市長), and other officials designated by law or deemed necessary by the Chairperson of the Cabinet can also attend the Cabinet meetings and speak in front of the Cabinet without the right to vote on the matters discussed in the meetings  The Mayor of Seoul, although being the head of a local autonomous region in South Korea and not directly related to the central executive branch, has been allowed to attend the Cabinet meeting considering the special status of Seoul (Special City) and its mayor (the only cabinet-level mayor in Korea).
It has to be noted that the Cabinet of the Republic of Korea performs somewhat different roles than those of many other nations with similar forms. As the Korean political system is basically a presidential system yet with certain aspects of parliamentary cabinet system combined, the Cabinet of the Republic of Korea also is a combination of both systems. More specifically, the Korean Cabinet performs policy resolutions as well as policy consultations to the President. Reflecting that the Republic of Korea is basically a presidential republic the Cabinet resolutions cannot bind the president's decision, and in this regard the Korean Cabinet is similar to those advisory counsels in strict presidential republics. At the same time, however, the Constitution of the Republic of Korea specifies in details 17 categories including budgetary and military matters, which necessitates the resolution of the Cabinet in addition to the President's approval, and in this regard the Korean Cabinet is similar to those cabinets in strict parliamentary cabinet systems.
The official residence and office of the President of the Republic of Korea is Cheongwadae (청와대, 靑瓦臺), located in Jongno-gu, Seoul. The name "Cheongwadae" literally means "the house with blue-tiled roof" and is named as such due to its appearance. The president is assisted in his or her duties by the Prime Minister of South Korea as well as the Presidential Secretariat (대통령비서실, 大統領祕書室). In addition to the Office of the President, Cheongwadae (청와대, 靑瓦臺) also houses the Office of National Security (국가안보실, 國家安保室) and the Presidential Security Service (대통령경호실, 大統領警護室) to assist the President. The Prime Minister is appointed by the president upon the approval of the National Assembly, and has the power to recommend the appointment or dismissal of the Cabinet ministers. The Prime Minister is assisted in his/her duties by the Prime Minister's Office which houses both the Office for Government Policy Coordination (국무조정실, 國務調整室) and the Office of the Prime Minister (국무총리비서실, 國務總理祕書室), the former of which is headed by a cabinet-level minister and the latter by a vice minister-level chief of staff. In the event that the president is unable to fulfill his duties, the Prime Minister assumes the president's powers and takes control of the state until the President can once again fulfill his/her duties or until a new president is elected.
Currently 18 ministries exist in the South Korean government. The 18 ministers are appointed by the President and report to the Prime Minister. Also, some ministries have affiliated agencies (listed below), which report both to the Prime Minister and to the minister of the affiliated ministry. Each affiliated agency is headed by a vice-minister-level commissioner except Prosecution Service which is led by a minister-level Prosecutor General.
The Minister of Strategy and Finance and the Minister of Education, by law, automatically assumes the position of Deputy Prime Minister of the Republic of Korea.
The respective ministers of the below ministries assume the President's position in the below order, in the event that the President cannot perform his/her duty and the Prime Minister cannot assume the President's position. Also note that the Constitution and the affiliated laws of the Republic of Korea stipulates only so far as the Prime Minister and the 17 ministers as those who can assume the President's position. Moreover, in the event that the Prime Minister cannot perform his/her duty the Vice Prime Minister will assume the Prime Minister's position, and if both the Prime Minister and the Vice Prime Minister cannot perform the Prime Minister's role the President can either pick one of the 17 ministers to assume the Prime Minister's position or let the 17 ministers assume the position according to the below order.
The commissioner of National Tax Service, a vice-minister-level official by law, is customarily considered to be a minister-level official due to the importance of National Tax Service. For example, the vice-commissioner of the agency will attend meetings where other agencies would send their commissioners, and the commissioner of the agency will attend meetings where minister-level officials convene.
The following agencies report directly to the President:
The following councils advise the president on pertinent issues:
The following agencies report directly to the Prime Minister:
Until recently almost all of the central government agencies were located in either Seoul or Gwacheon government complex, with the exception of a few agencies located in Daejeon government complex. Considering that Gwacheon is a city constructed just outside Seoul to house the new government complex, virtually all administrative functions of South Korea were concentrated in Seoul. It has been recently decided, however, that the majority of the government agencies relocate themselves to Sejong Special Self-Governing City established in South Chungcheong Province so that the government agencies are better accessible from most parts of South Korea and at the same time the concentration into Seoul might be deterred. So far only the first phase of the project has been finished and the selected agencies will move one by one to the new government complex in Sejong City during the next few years. Here is a brief description of where the agencies will settle when the project is finished.
The following agencies will settle in Seoul government complex:
The following agencies will settle in Seoul, but in separate locations:
The following agencies will settle in Gwacheon government complex:
The following agencies will settle in Daejeon government complex:
The following agencies will settle in Sejong government complex:
The following agencies will settle in separate locations:
The judicial branch includes the Supreme Court, the Constitutional Court, regional appellate courts, and local district, branch, municipal, and specialized courts. All courts are under the jurisdiction of the national judiciary; independent local courts are not permitted. Judges throughout the system are required to have passed a rigorous training system including a two-year program and two-year apprenticeship. All judicial training is provided through the Judicial Research and Training Institute, and is limited to those who have already passed the National Judicial Examination.
The Supreme Court is the head of the judicial branch of government and the final court of appeal for all cases in South Korean law. The Supreme Court, seated in Seoul, consists of fourteen Justices, including one Chief Justice. The Chief Justice of the Supreme Court has the power over all court administration, and can recommend court-related legislation to the National Assembly. The Justices must be at least 40 years old, and have at least 15 years of experience practicing law. They serve for six-year terms; the Chief Justice cannot be reappointed, but the other justices can.
Below the Supreme Court come appellate courts, stationed in five of the country's major cities. Appellate courts typically consist of a panel of three judges. Below these are district courts, which exist in most of the large cities of South Korea. Below these are branch and municipal courts, positioned all over the country and limited to small claims and petty offenses. Specialized courts also exist for family, administrative, and patent cases.
The Constitutional Court, independent from the Supreme Court, is charged purely with constitutional review and with deciding cases of impeachment. Other judicial matters are overseen by the Supreme Court. This system was newly established in the Sixth Republic, to help guard against the excesses shown by past regimes. The Constitutional Court consists of nine judges. Of these, three are recommended by the Chief Justice of the Supreme Court, three by the National Assembly, and three by the president; however, all must be appointed by the president. The President of the Constitutional Court is appointed by the national president, subject to the approval of the National Assembly. The members of the court serve for six-year renewable terms, and cannot be older than 65 (except for the President of the court, who may be as old as 70).
Because the Constitution of the Republic of Korea defines the territory of South Korea as "the Korean Peninsula and its adjacent islands," the courts of South Korea have allowed representatives of North Koreans to appear in South Korean courts with respect to inheritance in cases of deceased South Koreans with North Korean heirs. Funds are held in trust and dispersed only with government approval.
Elections in South Korea are held on national level to select the President and the National Assembly. South Korea has a multi-party system, with two dominant parties and numerous third parties. Elections are overseen by the Electoral Branch, National Election Commission (Republic of Korea). The most recent presidential election was held on 9 May 2017.
The president is directly elected for a single five-year term by plurality vote. The National Assembly has 300 members elected for a four-year term, 253 in single-seat constituencies and 47 members by proportional representation. Each individual party willing to represent its policies in the National Assembly must be qualified on the legislative (general) election that: i) if the national party-vote reaches over 3.00% on proportional contest or ii) if more than 5 members of their party that has been elected in each of their first-past-the-post election constituencies.
National Human Rights Commission of Korea (국가인권위원회, 國家人權委員會), by law, is guaranteed an independent status regarding all human rights issues in Korea. To ensure its independent status it is legally separated from all three branches (legislative, executive, judicial) of the government of South Korea. Moreover, to further ensure its independence, 4 of 11 commissioners are chosen by the National Assembly, another 4 by the President, and the rest 3 by the Chief Justice, so that no branch can hold the majority in the commission.
Local autonomy was established as a constitutional principle of South Korea beginning with the First Republic. However, for much of the 20th century this principle was not honored. From 1965 to 1995, local governments were run directly by provincial governments, which were run directly by the national government. However, since the elections of 1995, a degree of local autonomy has been restored. Local magistrates and assemblies are elected in each of the primary and secondary administrative divisions of South Korea, that is, in every province, metropolitan or special city, and district. Officials at lower levels, such as eup and dong, are appointed by the city or county government.
As noted above, local autonomy does not extend to the judicial branch. It also does not yet extend to many other areas, including fire protection and education, which are managed by independent national agencies. Local governments also have very limited policy-making authority; generally, the most that they can do is decide how national policies will be implemented. However, there is some political pressure for the scope of local autonomy to be extended.
Although the chief executive of each district is locally elected, deputy executives are still appointed by the central government. It is these deputy officials who have detailed authority over most administrative matters.
The South Korean civil service is managed by the Ministry of Personnel Management. This is large, and remains a largely closed system, although efforts at openness and reform are ongoing. In order to gain a position in civil service, it is usually necessary to pass one or more difficult examinations. Positions have traditionally been handed out based on seniority, in a complex graded system; however, this system was substantially reformed in 1998.
There are more than 800,000 civil servants in South Korea today. More than half of these are employed by the central government; only about 300,000 are employed by local governments. In addition, only a few thousand each are employed by the national legislative and judicial branches; the overwhelming majority are employed in the various ministries of the executive branch. The size of the civil service increased steadily from the 1950s to the late 1990s, but has dropped slightly since 1995.
The civil service, not including political appointees and elected officials, is composed of career civil servants and contract civil servants. Contract servants are typically paid higher wages and hired for specific jobs. Career civil servants make up the bulk of the civil service, and are arranged in a nine-tiered system in which grade 1 is occupied by assistant ministers and grade 9 by the newest and lowest-level employees. Promotions are decided by a combination of seniority, training, and performance review. Civil servants' base salary makes up less than half of their annual pay; the remainder is supplied in a complex system of bonuses. Contract civil servants are paid on the basis of the competitive rates of pay in the private sector.