On September 28, 2004, APCO announced its independent buyout from Grey Global and has thus become one of the largest privately owned public relations firms in the world.

[13] WorldCom hired APCO Worldwide to handle its political PR surrounding the media frenzy regarding its disclosure that £2.4bn in expenses had been falsely reported in its financial results in 2002.

[16] The "Sound Science Coalition" (TASSC) was created in 1993 by Phillip Morris and APCO in response to a 1992 United States Environmental Protection Agency (EPA) report[17] which identified secondhand smoke as a Group A human carcinogen.

[18][19] TASSC developed local coalitions to influence media, legislators, and the public, and recruited scientists and researchers to support Philip Morris's position.

During this same meeting, he contemplated that HP would negatively be affected by bad press of its CEO being involved in an inappropriate relationship with an ex-soft porn actress, Jodie Fisher.

[25] In September 2024, the London headquarters of APCO was targeted by Palestine Action over its representation of the UK interests of Israeli arms firm Elbit Systems.