In most business contexts, Madison Avenue refers to the major ADVERTISING agencies with offices on Madison Avenue in New York City. It is also a major retail shopping district in the city. During the 20th century, New York City dominated world financial markets, was headquarters for most U.S. businesses, and competed with Paris as the center of Western fashion design. Advertising agencies evolved in New York City to support the MARKETING COMMUNICATIONS needs of major companies located there. During the latter part of the 20th century, many U.S. companies moved their headquarters out of New York and at the same time became MULTINATIONAL CORPORATIONs (MNCs). Most Madison Avenue agencies retained offices in the city but merged with other ad agencies in order to service multinational clients. Madison Avenue agencies are mostly named after the individuals and groups who founded them: Ogilvy & Mather; Young & Rubicam; J. Walter Thompson; Leo Burnett; and Saatchi & Saatchi. In recent years these and other agencies have merged, creating global marketing services firms such as WPP and Omnicom.