The Plaza Accord preceded the U.S. dollar’s sharp decline before the 1987 stock-market crash. Signed on September 22, 1985, at New York’s Plaza Hotel, the agreement involved the United States, Japan, West Germany, France, and the United Kingdom.
The countries agreed that the dollar had become too strong and that coordinated action should encourage its depreciation. The dollar subsequently fell substantially against the Japanese yen and the German mark. The agreement is therefore an important part of the international background to the mid-1980s financial environment.
The Plaza Accord did not directly cause Black Monday. The 1987 crash also involved interest rates, trade disputes, market valuations, portfolio insurance, and trading-system pressures. A later 1987 agreement, often called the Louvre Accord, sought to stabilize exchange rates. Confusing these two accords can obscure the different goals of coordinated currency policy before and after the crash.