Prior to the creation of the European Aviation Safety Agency, now called the European Union Aviation Safety Agency (EASA), the Joint Aviation Authorities (JAA) was responsible for publishing regulations governing the operations, maintenance, licensing and certification/design standards for all classes of aircraft. These regulations were introduced after long consultation to achieve common ground between the states involved. These regulations are known as Joint Aviation Requirements (JARs).
JARs had no legal status until they were ratified by national governments, but many European countries adopted all or part of JARs as the basis for their own national regulations. With the creation of EASA, JARs were amended as necessary and brought into EU legislation so that they are binding on all EU nations.