Ketchum Inc.

The agency that would become Ketchum was founded as Ketchum and MacLeod in Pittsburgh on May 22, 1923. The agency's name was changed to Ketchum, MacLeod & Grove in 1924. It was led by brothers George and Carlton Ketchum, and Norman McLeod and Robert Grove, whom the brothers met at University of Pittsburgh in the 1910s. The agency's early work focused on advertising, publicity, and fundraising.

In 1934 the agency established a public relations department. The department's first assignment was a campaign for Natural Gas Companies, People's Natural Gas, and other local natural gas companies. The agency received national attention in 1951 when it orchestrated a sponsorship for client Westinghouse of the first nationally televised NCAA football game. As the firm's billings grew in the late 1950s, it opened offices in New York City and Washington, D.C. It acquired west coast-based agency Botsford Constantine & McCarty, forming Botsford-Ketchum in 1969.

George Ketchum died in September 1975. The agency changed its name to Ketchum Communications Inc. in 1981. Its major divisions became known as Ketchum Advertising, Ketchum Public Relations, and Ketchum Directory Advertising. Ketchum Public Relations moved its headquarters to New York from Pittsburgh in 1982.

The agency won its first global account (with FedEx) and its first pan-European account (with Whirlpool) in 1994. In 1996, Ketchum handled the Torch relay for the Atlanta Olympics.

In 2016, Ketchum created "Cultivate", a new branch to help companies and organizations in organic food markets.

In November 2017, Ketchum announced that then Partner and President Barri Rafferty would assume the role of president and chief executive officer, effective January 1, 2018. Rafferty is the first woman to lead a top five global public relations firm.

Omnicom Group acquired Ketchum in 1996. At the time, Ketchum was the 25th-largest American agency. In 1998, Ketchum merged with British consumer agency Life PR. Ketchum sold Ketchum Advertising in 1999; the "Ketchum" name has referred solely to the PR practice since that time.

In the 2000s, Ketchum acquired several firms and opened others, including the acquisition of New York management consulting firm Stromberg Consulting in 2001, the launching of influencer marketing and community building firm Emanate in 2006, and the acquisitions of clinical trial patient recruitment agency MMG in 2008, Moscow-based Maslov PR in 2010, Indian agency Sampark PR in 2011, Capstrat in North Carolina in 2012, and German lifestyle and social media PR agency Brandzeichen in 2013. Ketchum took a majority stake in Newscan's China operations in 2011, expanded Ketchum Sports & Entertainment practice into Brazil in 2012, and acquired ICON International Communications in Singapore in 2013. In the US, Ketchum partnered with luxury and lifestyle agency Harrison & Shriftman in 2011, and launched music marketing service Ketchum Sounds in 2012.

Ketchum merged with Düsseldorf-based Pleon in one of the industry's largest mergers in 2009, and later merged with South Korea-based firm InComm Brodeur in 2013.

In February 2026, Omnicom Public Relations announced a restructuring of its portfolio, and as part of the changes, Ketchum and Golin, an agency owned by Interpublic Group (IPG), merged to form a combined global brand communications agency. The restructuring also included the integration of Porter Novelli into FleishmanHillard. According to Omnicom Public Relations, the changes were designed to create a more integrated communications organization while maintaining continuity for existing clients.