Omnicom Group Inc. is an American global media, marketing, and corporate communications holding company, headquartered in New York City.
Omnicom's branded networks and specialty firms provide services in four disciplines: advertising, customer relationship management (CRM), public relations, and specialty services. The services included in these disciplines are media planning and buying, digital and interactive marketing, sports and events marketing, field marketing, and brand consultancy.
WPP plc is a British multinational communications, advertising, public relations, technology, and commerce holding company headquartered in London, England. It is the world's largest advertising company, as of 2023. WPP plc owns many companies, which include advertising, public relations, media, and market research networks such as AKQA, Burson, Hogarth, Landor, Ogilvy, VML, and WPP Media (EssenceMediacom, Mindshare, Wavemaker, choreograph and more). It is one of the "Big Three" agency companies, alongside Publicis and Omnicom. WPP has a primary listing on the London Stock Exchange, and is a constituent of the FTSE 100 Index.
Publicis Groupe S.A. is a French multinational advertising and public relations company. As of 2024, the company is the largest advertising company in the world by revenue. Based in Paris, it is one of the 'Big Four' advertising companies, alongside WPP, Interpublic and Omnicom. Publicis Groupe S.A. is headed by Arthur Sadoun, and its agencies provide digital and traditional advertising, media services and marketing services to national and multinational clients.