Kunrei-shiki rōmaji (訓令式ローマ字?) is a Cabinet-ordered, Japanese romanization system, i.e. a system for transcribing the Japanese language into the Latin alphabet. It is abbreviated as Kunrei-shiki. Its name is rendered Kunreisiki using Kunrei-shiki itself. Kunrei-shiki is sometimes known as the Monbushō system in English, because it is taught in the Monbushō-approved elementary school curriculum. The ISO has standardized Kunrei-shiki under ISO 3602.
Kunrei-shiki is based on the older Nihon-shiki (Nipponsiki) system, modified for modern standard Japanese. For example, the word かなづかい, romanized kanadukai in Nihon-shiki, is pronounced kanazukai in common modern Japanese, and Kunrei-shiki uses the latter spelling. Kunrei-shiki competes with the older Hepburn romanization system, which was promoted by the authorities during the occupation of Japan.
In the period before World War II there was a political conflict between supporters of Hepburn romanization and supporters of Nihon-shiki romanization. In 1930 a board of inquiry under the aegis of the Minister of Education was established to determine the proper romanization system. The Japanese government, by cabinet order (訓令 kunrei), announced on September 21, 1937 that a modified form of Nihon-shiki would be officially adopted as Kunrei-shiki. The form at the time differs slightly from the modern day form. Originally the system was called the Kokutei (国定, government-authorized) system.