MCI can stand for Microwave Communications Incorporated, which formerly was Worldcom. It was the #2 long-distance provider in the United States; the early history is discussed below. It merged with WorldCom, Inc in 1998 for US $34.7 billion, creating MCI WorldCom. MCI WorldCom dropped the "MCI" from its name in 2000, becoming simply WorldCom. More recently, in light of a huge accounting scandal, new WorldCom was renamed MCI. MCI thus refers both to one of the companies entering into the merger between MCI and WorldCom, as well as to the resulting entity.
In 1963, Microwave Communications, Inc. was formed by John Goeken to offer long-distance telephone service for businesses between Chicago, Illinois and St. Louis, Missouri. The company became licensed by the Federal Communications Commission in 1969 and began service under the new name MCI Communications in 1970.
In 1991, British Telecommunications PLC purchased 20% of the company and later made an offer to purchase the rest in 1996. A larger, competing bid from WorldCom was ultimately accepted after British Telcom significantly lowered the price of their offer.
After an internal audit discovered that US$3.8 billion had been 'misaccounted.' and a investgation by the Securities and Exchange Commission, the company has changed its name to MCI and moved its headquarters from Clinton, Mississippi to Ashburn, Virginia.
See also: WorldCom