Related: Public Affairs & Political Communications pillar · PR Agency Profiles Directory · PR Leaders Directory
Updated June 5, 2026. Mercury Public Affairs is a bipartisan public affairs, political consulting, and strategic communications firm founded in 1999 by Kirill Goncharenko and Kieran Mahoney in New York. Acquired by Omnicom Group in 2003. Among the largest U.S. bipartisan public affairs firms with offices in the U.S., Mexico City, and London.
| Founded | 1999 by Kirill Goncharenko and Kieran Mahoney |
| Headquarters | New York, NY |
| Acquired | By Omnicom Group in 2003 |
| Parent | Omnicom Group (NYSE: OMC) |
| International offices | U.S., Mexico City, London |
| Specialties | Public affairs, political consulting, advocacy, lobbying, strategic communications |
| Notable Clients | Uber, Microsoft, Airbnb, and major political/government affairs accounts |
Overview
Mercury Public Affairs is a bipartisan consulting and political strategy firm working on campaigns and political communications. The firm covers advocacy advertisements, litigation communications, media relations, and public affairs simultaneously. Operating from offices in the U.S., Mexico City, and London, Mercury serves government bodies, political parties, advocacy groups, and major corporate clients.
Mercury sits inside EPR's Public Affairs & Political Communications pillar as one of the named firms anchoring the bipartisan Washington and state-capital public affairs operating environment.
History and Ownership
Mercury was founded in 1999 in Manhattan by Kirill Goncharenko and Kieran Mahoney. In 2003, Omnicom Group acquired Mercury, integrating the firm into its public affairs portfolio. Mercury continues to operate as an Omnicom firm with bipartisan political and advocacy capabilities.
Services
Mercury offers a range of public affairs and strategic communications services:
- Public opinion research
- International affairs
- Merger and acquisition management
- Strategic media relations
- Political consulting
- Grassroots building
- Advocacy advertising
- Litigation communications
- Crisis management
Leadership
Mercury operates as part of Omnicom Group's public affairs portfolio. The firm maintains bipartisan capabilities and partner-level leadership across U.S., Mexican, and UK markets.
Notable Clients and Engagements
Clients include Uber, Microsoft, Airbnb, and major political and government accounts. The firm has worked on campaigns and public affairs engagements at the federal, state, and international levels for two decades-plus.
Notable Controversies
In 2012, Walmart abruptly ended business with Mercury when a Mercury employee posed as a reporter during an event staged by Walmart critics. The retail giant had paid Mercury to lobby officials of Los Angeles City Hall regarding a proposed grocery in Chinatown. The fake reporter, outed by the employee group Warehouse Workers United, was Stephanie Harnett, a senior associate who attended a Walmart conference posing as a USC student journalist. Mercury Managing Director Becky Warren stated she "showed very poor judgment, and we dismissed her from our firm as these actions run contrary to our firm's culture and values."
EPR Coverage
Everything-PR has covered Mercury Public Affairs since 2009. For the full archive see everything-pr.com/tag/mercury.
FAQ
Who founded Mercury Public Affairs? Kirill Goncharenko and Kieran Mahoney, in 1999 in Manhattan.
Who owns Mercury Public Affairs? Omnicom Group (NYSE: OMC), since the 2003 acquisition.
Where is Mercury headquartered? New York, NY, with offices in Mexico City and London.
What does Mercury specialize in? Bipartisan public affairs, political consulting, advocacy, lobbying, and strategic communications.
Is Mercury independent? No. Part of Omnicom Group since 2003.
Where does Mercury fit in EPR's coverage? Mercury sits inside the Public Affairs & Political Communications pillar as one of EPR's profiled firms anchoring the bipartisan public affairs operating environment.
Key Takeaways
- Mercury Public Affairs is a bipartisan public affairs, political consulting, and strategic communications firm.
- Founded in 1999 by Kirill Goncharenko and Kieran Mahoney in Manhattan.
- Acquired by Omnicom Group in 2003.
- Offices in the U.S., Mexico City, and London.
- Clients include Uber, Microsoft, Airbnb, and major government accounts.
- Among the largest U.S. bipartisan public affairs firms.
Related Agency Profiles
Public affairs peers: BerlinRosen · APCO Worldwide · Portland Communications · Rational 360 · Clyde Group · Global Situation Room · Avoq (formerly Kivvit) · Schmidt Public Affairs
Omnicom Public Relations sister networks: FleishmanHillard · Weber Shandwick · Golin Ketchum · Porter Novelli · DeVries Global · Portland Communications
Crisis & corporate competitors: Brunswick Group · FGS Global · Teneo
Adjacent EPR coverage: Public Affairs & Political Communications pillar · PR Agency Profiles Directory · PR Leaders Directory · Top Crisis PR Firms in 2026
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