National Diet Building

The National Diet (Japanese: 国会, Hepburn: Kokkai) is Japan's bicameral legislature. It is composed of a lower house, called the House of Representatives (衆議院, Shūgiin), and an upper house, the House of Councillors (参議院, Sangiin). Both houses are directly elected under a parallel voting system. In addition to passing laws, the Diet is formally responsible for selecting the Prime Minister. The Diet was first convened as the Imperial Diet in 1890 under the Meiji Constitution, and took its current form in 1947 upon the adoption of the post-war constitution. Both houses meet in the National Diet Building (国会議事堂, Kokkai-gijidō) in Nagatachō, Chiyoda, Tokyo.

The House of Representatives (衆議院, Shūgiin) is the lower house of the National Diet of Japan. The House of Councillors is the upper house. The composition of the House is established by Article 41 (ja) and Article 42 (ja) of the Constitution of Japan. The House of Representatives has 465 members, elected for a four-year term. Of these, 176 members are elected from 11 multi-member constituencies by a party-list system of proportional representation, and 289 are elected from single-member constituencies. 233 seats are required for a majority. The overall voting system used to elect the House of Representatives is a parallel system, a form of semi-proportional representation. Under a parallel system the allocation of list seats does not take into account the outcome in the single seat constituencies. Therefore, the overall allocation of seats in the House of Representatives is not proportional, to the advantage of larger parties. In contrast, in bodies such as the German Bundestag or the New Zealand Parliament the election of single-seat members and party list members is linked, so that the overall result respects proportional representation fully or to some degree.The House of Representatives is the more powerful of the two houses, able to override vetoes on bills imposed by the House of Councillors with a two-thirds majority.The last election for the House of Representatives was held on 31 October 2021 in which the Liberal Democratic Party won a majority government with 261 seats. Along with their coalition partner, Komeito, which won 32 seats, the governing coalition holds 293 seats in total.

The House of Councillors (参議院, Sangiin) is the upper house of the National Diet of Japan. The House of Representatives is the lower house. The House of Councillors is the successor to the pre-war House of Peers. If the two houses disagree on matters of the budget, treaties, or designation of the prime minister, the House of Representatives can insist on its decision. In other decisions, the House of Representatives can override a vote of the House of Councillors only by a two-thirds majority of members present. The House of Councillors has 245 members who each serve six-year terms, two years longer than those of the House of Representatives. Councillors must be at least 30 years old, compared with 25 years old in the House of Representatives. The House of Councillors cannot be dissolved, and terms are staggered so that only half of its membership is up for election every three years. Of the 121 members subject to election each time, 73 are elected from 45 districts by single non-transferable vote (SNTV) and 48 are elected from a nationwide list by proportional representation (PR) with open lists.

Kokkai-gijidomae Station (国会議事堂前駅, Kokkai-gijidō-mae-eki) is a subway station in Chiyoda, Tokyo, Japan, operated by the Tokyo subway operator Tokyo Metro. It is located adjacent to the National Diet Building. The station name literally means "in front of the National Diet Building".

Zasshi Kiji Sakuin (雑誌記事索引, "Japanese Periodicals Index"), often called Zassaku in short, is a searchable database of scholarly articles in Japanese. The database, produced by the National Diet Library (NDL) in 1948, catalogs selected articles from NDL's extensive collection of periodicals. The database was created for the purpose of facilitating scholastic research in providing citation information. Scholarly journals, specialized magazines, institutional periodical publications and general-interest magazines are included in the database from all areas of academic interest: humanities, social sciences, science and technology, and medical sciences, including pharmacology. Approximately 10,000 periodicals and more than 6,660,000 articles are currently registered in Zasshi Kiji Sakuin. It is updated every two weeks. Zasshi Kiji Sakuin's extensive coverage of periodicals provides an excellent bibliography of research and publications in Japan, which may not necessarily appear in non-Japanese journals of Japanese studies.

The National Diet Library (NDL) (国立国会図書館, Kokuritsu Kokkai Toshokan) is the national library of Japan and among the largest libraries in the world. It was established in 1948 for the purpose of assisting members of the National Diet of Japan (国会, Kokkai) in researching matters of public policy. The library is similar in purpose and scope to the United States Library of Congress. The National Diet Library (NDL) consists of two main facilities in Tokyo and Kyoto, and several other branch libraries throughout Japan.

The Cabinet Office (内閣府, Naikaku-fu) (CAO) is an agency of the Cabinet of Japan. It is responsible for handling the day-to-day affairs of the Cabinet. The Cabinet Office is formally headed by the Prime Minister.

The Cabinet Secretariat (内閣官房, Naikaku-kanbō) is an agency in the Japanese government, headed by the Chief Cabinet Secretary. It organizes the Cabinet's public relations, coordinates ministries and agencies, collects intelligence, and organizes miscellaneous other tasks for the Cabinet, including the Prime Minister's office (Kantei) and residence (Kōtei).

The Prime Minister's Official Residence is the official workplace and residence of the Prime Minister of Japan. It is commonly referred to as Sōri Daijin Kantei (総理大臣官邸), Shushō Kantei (首相官邸), or simply Kantei (官邸). Located at 2-3-1 Nagata-chō, Chiyoda-ku, Tokyo 100–8968, it is diagonally adjacent to the National Diet Building.The term Kantei is used as a metonym for the office of the Prime Minister of Japan and for the Prime Minister's advisors and administration in general. In addition to being the principal office and residence of the Prime Minister, the building also serves as the principal office of the Chief Cabinet Secretary and their Deputy, the location of Cabinet meetings, and is also the location of a national crisis management center.

The May 15 Incident (五・一五事件, Goichigo Jiken) was an attempted coup d'état in the Empire of Japan, on May 15, 1932, launched by reactionary elements of the Imperial Japanese Navy, aided by cadets in the Imperial Japanese Army and civilian remnants of the ultranationalist League of Blood (Ketsumei-dan). Prime Minister Inukai Tsuyoshi was assassinated by 11 young naval officers. The following trial and popular support of the Japanese population led to extremely light sentences for the assassins, strengthening the rising power of Japanese militarism and weakening democracy and the rule of law in the Empire of Japan.

The Cabinet Legislation Bureau (内閣法制局, naikakuhōseikyoku) is a Japanese government agency which advises Cabinet members on drafting legislation to be proposed to the Diet. It acts as legal counsel for the Cabinet by examining bills, orders, and treaties. It also presents opinions on legal matters to the Prime Minister and other Cabinet Ministers.

The Imperial College of Engineering (工部大学校, Kōbudaigakkō) was a Japanese institution of higher education that was founded during the Meiji Era. The college was established under the auspices of the Ministry of Public Works for the training of young Japanese engineers. Supporting Japan’s rapid industrialization at the end of the 19th century, the college commenced teaching in October 1873 soon after the initial cohort of teaching staff arrived from United Kingdom. The college was an immediate precursor to the establishment of the University of Tokyo’s Faculty of Engineering in 1877.