A gentlemen`s agreement, or gentleman`s agreement, is an informal and legally non-binding agreement between two or more parties. It is usually oral, but it can be written or simply understood as part of a tacit agreement by convention or by mutually beneficial label. The essence of a gentlemen`s agreement is that it depends on the honour of the parties for its achievement, rather than being enforceable in one way or another. It differs from a legal agreement or a contract. Gentlemen`s agreements were a widespread discriminatory tactic, which would have been more common than restrictive alliances to maintain the homogeneity of upper-class neighborhoods and suburbs in the United States.  The nature of these agreements made it extremely difficult to prove or follow them, and they were long after the U.S. Supreme Court decisions in Shelley/. Kraemer and Barrows v. Jackson.  A source indicates that the gentlemen`s agreements are “probably still in place” but that their use has declined sharply.  In the automotive industry, Japanese manufacturers have agreed that no standard vehicle would have more than 276 hp (206 kW; 280 hp); The agreement ended in 2005.  German manufacturers limit the maximum speed of high-performance sedans (berlines) and breaks to 250 km/h.
  When the Suzuki Hayabusa motorcycle exceeded 310 km/h in 1999, fears of a European ban or regulatory intervention led Japanese and European manufacturers to limit to 300 km/h at the end of 1999 See list of the fastest series bikes. In English contract law, for it to be binding, an agreement must have the intention of establishing legal relations; but in commercial transactions (i.e. agreements that do not exist between family members or friends), there is a legal presumption of “intent to establish legal relations”. In the 1925 case of Rose and Frank Co. v. JR Crompton – Bros Ltd., however, the House of Lords found that the phrase ” “This regulation is not … a formal or legal agreement … is only a record of the parties` intention “was sufficient to rebut this presumption.  Japan was prepared to restrict immigration to the United States, but was seriously injured by San Francisco`s discriminatory law, which specifically targeted its people.
President Roosevelt, who wanted to maintain good relations with Japan as a pole opposed to Russian expansion in the Far East, intervened. While the U.S. ambassador reassured the Japanese government, Roosevelt summoned the mayor and the San Francisco school board to the White House in February 1907 and convinced him to end segregation and promised that the federal government itself would address the issue of immigration. On February 24, the gentlemen`s agreement was reached with Japan in the form of a Japanese memo that agreed to deny passports to workers entering the United States and recognizing the United States.